The challenges of analysing island publications in several languages via metadata search results on WORLDCAT are that material comes from various libraries and is not consistently tagged, that some languages had more spelling variants and lexical variants in the early modern period than others, and that the search parametres may retrieve false negatives if words occur in several languages with different meanings.

This why an initial analysis in search results per language using different word forms and WORLDCAT search fields were carried out to identify and interpret the output deviations.

1) “ISLAND(S)” in different languages:

Language	Singular	Plural	Genitive	Other cases	ti: 1600-1800: all	su: 1600-1800: all	ti: own language	su: own language	su: English search	National catalogue	Results national	Comments
Turkish	ada	adalar	adanın	adaya	172	47	4	0	1	#	#	No Ottoman Turkish words are tagged in modern Turkish. 3 works in Ottoman Turkish were found with modern titles. 41 results in title search have no defined language.
Friesian	eilân	eilannen	no declination	no declination	3	2	0	0	0	#	#
Scots Gaelic	eilean	eileanan	eilein	eilean	3	2	3	0		Jisc Library Hub	9	Two of the books were printed in Duneidin, one in Glasgow. The oldest work listed is: Comh-chruinneachidh orannaigh Gaidhealach, le Raonuill MacDomhnuill, aunn ‘n Eilean Eigg. Vol. I., by Ronald MacDonald, of the Isle of Eigg.; Angus MacGillivray, of MacGillivray; Duneidiunn : Clo-bhuailt ann le Walter Ruddiman, M, DCC, LXXVI. [1776]
Icelandic	eyja	eyjar	eyjunni	#	2	0	0	0	32	#	#	Both results are in fact written in Danish.
Maltese	gżira	gżejjer	#	#	0	0	0	0	0	#	#
French	îles	îles	#	#	154,334	17,394	72721	10349	1817	BNF catalogue générale	19363	Results for “isle” still include many results in English?? SUDOC has only 1127 results?
Portuguese	ilha	ilhas	#	#	#	#	#	#	40	PORBASE	> 5218	Most results are in Spanish, partly tagged in Portuguese.
Portuguese	isla	islas	#	#	#	#	#	#	40	PORBASE	> 5218	Most results are in Spanish, partly tagged in Portuguese.
German	insel	inseln	#	#	7,121	1,205	6303	119	441	K10plus	2.326	370 items have no identified language!
Luxemburgish	Insel	Inselen	#	#					0	#	#
German	insul	insuln	#	#	7,121	1,205	6303	119	441	K10plus	2.326	370 items have no identified language!
Latin	insula	insulae	insularum	insulam	9,356	8	5707	4	742	#	#	Inclusion of different cases makes a huge difference in title search by circa 3000 items! On the other hand, no library uses tags in Latin.
Romanian	insulă	insule	#	#	3,150	5	0	0	0	#	#	The majority of results in title search are in Latin.
Basque	irla	uharteak	#	#	1	0	0	0	0	#	#	The only result found is in Spanish.
Albanian	ishull	ishujt	#	#	0	0	0	0	0	#	#
Spanish	isla	islas	#	#	7,822	1,136	5502	563	315	Spanish National LIbrary	2517	Catálogo Colectivo REBIUN: Interner Fehler beim Verbindungsaufbau.
Spanish (early modern)	ysla	yslas	#	#	7,822	1,136	5502	563	315	Spanish National LIbrary	2517	Catálogo Colectivo REBIUN: Interner Fehler beim Verbindungsaufbau.
French	isle	isles	#	#	154,334	17,394	72721	10349	1817	BNF catalogue générale	19363	Catálogo Colectivo REBIUN: Interner Fehler beim Verbindungsaufbau.
Italienisch	isola	isole	#	#					295	#	#
Arabic	jazira	aljuzur	#	#	0	0	0	0	2	#	#	PROBLEM: early modern Arabic may have used different words. Transliterations of non-Latin script may vary!!
Greek	nisí	nisiá	nisioú	nisión	1,721	87	10	0	3	#	#	Greek includes old and modern Greek. One result was in Ottoman Turkish plus Latin. Inclusion of all cases did not affect the search results.
Swedish	ö	öar	#	#	137,308	12,339	1647	6	17	#	#	PROBLEM: result list retrieves “ö” in many contexts.
Danish	ø	øer	#	#	137,443	12,684	501	88	279	#	#	125 results are in Scottish Gaelic, using “o” in the title in the meaning of “from”. Oldest Danish book: En kort dog fuldstændig Historie, af en Islænder ved Navn Arne Joensen, som Anno 1747 kom i Laug med et underjordisk Fruentimmer, og Derefter blev lykkeligen frelset af Hendes Snare, [S.l.], trykt i dette Aar.
Gaeilge	oileán	oileáin	oileán	no declination	0	0	0	0	0	#	#	PROBLEM: prior to the 20th century, Irish spelling was not normalised.
Ukrainian	ostriv	ostrovy	#	#	50	15	0	0	0	#	#	Results are Russian, Hebrew or in Western languages. Several results in English, Dutch etc. were tagged with slawic island names and thus showed up in the result list.
Slowakian	ostrov	ostrovy	#	#	50	15	0	0	0	#	#	Results are Russian, Hebrew or in Western languages. Several results in English, Dutch etc. were tagged with slawic island names and thus showed up in the result list.
Macedonian	ostrov	ostrovi	#	#	50	15	0	0	0	#	#	Results are Russian, Hebrew or in Western languages. Several results in English, Dutch etc. were tagged with slawic island names and thus showed up in the result list.
Russian	ostrov	ostrova	s ostrova	no declination	50	15	41	1	34	#	#	Most of the Russian results were printed in St. Petersburg. The oldest Russian result listed is the map “Kniga glagolemai︠a︡ kosmografii︠a︡ perevedena bystʹ s rimskago i︠a︡zyka v neī opisany gosudarstva i zemli i znatnye ostrova i v kotoroĭ chasti zhivut katorie li︠u︡di”, [Russia] : [publisher not identified], [17–]. Several results in English, Dutch etc. were tagged with slawic island names and thus showed up in the result list.
Czech	ostrov	ostrovy	#	#	50	15	0	0	0	#	#	Results are Russian, Hebrew or in Western languages. Several results in English, Dutch etc. were tagged with slawic island names and thus showed up in the result list.
Bosnian	ostrvo	ostrva	#	#	0	0	0	0	0	#	#	No library catalogues from Bosnia included?
Serbian	ostrvo	ostrva	#	#	0	0	0	0	0	#	#	No library catalogues from Serbia included?
Slowenian	otok	otoki	#	#	4	7	0	0	0	#	#	All results are foreign results in Slowenian libraries. The languages retrieved are Polish, Japanese and Mongolian.
Croatian	otok	otoci	s otoka	#	4	7	0	0	0	#	#	All results are foreign results in Slowenian libraries. The languages retrieved are Polish, Japanese and Mongolian.
Norwegian	øy	øyer	#	#	2,789	110	1	1	1	#	#	Oldest result: Christiani VI. has lineas offert Autor: Jens Aalborg; Joh Fr Clasen; Susanne Kraft; Christ Rud Müller; Ole Camstrup; Joh Bald Rud Heber; C Sehestedt; N Sass; J Posth; Hans Bloch; J G Obbenhausen; Thom Jensen; Ped Sparkiær; N Feddersen, Verlag: Christianiæ, 1733. The subject result is: Sogneprestenes manntall 1664-1666, by Øyer prestegjeld (Oppland)
Estonian	saar	saartel	#	#	512	66	0	0	0	#	#	Comparatively many Hebrew results on a different topic.
Finnish	saari	saarilla	#	#	512	66	0	0	0	#	#	Comparatively many Hebrew results on a different topic.
Latvian	sala	salas	#	#	4,350	6	0	0	0	#	#	Mostly Spanish results on different topics. One Ottoman Turkish result on different topic.
Lithuanian	sala	salos	#	#	4,350	6	0	0	0	#	#	Mostly Spanish results on different topics. One Ottoman Turkish result on different topic.
Hungarian	sziget	szigetek	#	#	12	17	3	2	0	#	#	8 works are German translations or bilingual publications. One of the Hungarian works is a “Marine map depicting the island of St. Ilona” created in around 1800.
Polish	wyspa	wyspy	z wyspy	na wyspę	24	106	15	13 with no language	0	#	#	14 German results retrieved here are German sources in Polish library catalogues. Inclusion of all cases does not affect the search results.
Ottoman Turkish				#					1	#	#
English	island	islands	no declination	no declination	58,742	16,849	28,763	11335	11335	Jisc Library Hub	7340 (for island)
Not defined	#	#	#	#	#	#	#	#	612	#	#
Dutch	eiland	eilanden	van het eiland	no declination	1,782	136	1154	65	482	#	#
Multilingual	#	#	#	#	#	#	#	#	162	#	#
Hebrew	#	#	#	#	#	#	#	#	10	#	#
Catalonian	illa	illes	#	#	4,943	188	5	5	3	#	#	The vast majority of results are in Spanish and Latin but come with Catalonian tags.
Welsh	ynys	ynysoedd	no declination	no declination	53	20	35	20	1	Jisc Library Hub	51	All works that are not Welsh are map / landscape engravings that include Welsh island / place names in English titles.
Church slawonic	#	#	#	#	#	#	#	#	1	#	#
Faröisch	#	#	#	#	#	#	#	#	1	#	#
Old Norse	#	#	#	#	#	#	#	#	1	#	#

2) Results for specific ISLAND NAMES:

In order to identify the best query structure, the following manual searches were carried out in Worldcat:

Query	Number of all results between 1600 and 1800	Number of German results	Oldest result
kw: island OR insula	52722	1123	Riddarholmskyrkan från nordost, by Erik Dahlbergh, ca. 1600
kw: island	49237	982	Portraits of Juan Rodriguez Cabrillo and Sebastian Viscaino, ca.1540 & ca.1600
su: island	15103	405	Samling af Kort af forskellige kartografer fra det 16. århundrede, 22: Saxonum regionis quatenus eius gentis … [Danmark, syd], by Christian Sgorothenus et al., ca. 1600
su: islands	15103	405	Samling af Kort af forskellige kartografer fra det 16. århundrede, 22: Saxonum regionis quatenus eius gentis … [Danmark, syd], by Christian Sgorothenus et al., ca. 1600
su: island OR insula	15107	405	Samling af Kort af forskellige kartografer fra det 16. århundrede, 22: Saxonum regionis quatenus eius gentis … [Danmark, syd], by Christian Sgorothenus et al., ca. 1600
su: insel	440	52	Polvs arcticvs siue tract[us] septentrionalis, by Matthias Quad and Johannes Bussemacher, Coloniæ/Köln: Ex officina typographica Jani Bussemechers, 1600
su: insel OR island	15522	455	Samling af Kort af forskellige kartografer fra det 16. århundrede, 22: Saxonum regionis quatenus eius gentis … [Danmark, syd], by Christian Sgorothenus et al., ca. 1600
su: Zypern	111	4
ti: Zypern	54	43
su: Cyprus	224	8
ti: Cyprus OR Zypern OR Chypre OR Cypria	907	69	Cyprus insula laeta choris, blandorum et mater amorum (map), sumptibus Ioannis Ianssonii (Amstelodami), 1600-1699
ti: Creta OR Kreta OR Candia	1,711	463
su: Crete	745	21	Candie. Par Beaulieu (Map, ca. 1600)
su: Creta	40	1	Candia, by Philippe Galle and Abraham Ortelius and Jan Baptista Vrients, Antuerpiae, apud Ioannem Bapt. Urientium, 1601
su: Candia	83	1	Spaggia della città di Candia (1612)
su: Islands Maps Early Works to 1800	2159
su: insul OR insula OR isle OR insel OR island OR inseln OR insuln OR isola OR ilha	17554	538	Samling af Kort af forskellige kartografer fra det 16. århundrede, 22: Saxonum regionis quatenus eius gentis … [Danmark, syd], by Christian Sgorothenus et al., ca. 1600
kw: insul OR insula OR isle OR insel OR island OR inseln OR insuln OR isola OR ilha	95376	7696	Riddarholmskyrkan från nordost, by Erik Dahlbergh, ca. 1600
ti: insul OR insula OR isle OR insel OR island OR inseln OR insuln OR isola OR ilha	59923	6598	Riddarholmskyrkan från nordost, by Erik Dahlbergh, ca. 1600
ti:/su: insul OR insula OR isle OR insel OR island OR inseln OR insuln OR isola OR ilha	58567	5391	Riddarholmskyrkan från nordost, by Erik Dahlbergh, ca. 1600

3) Deductions for the best possible QUERY STRUCTURE:

Title searches retrieved very high results for word stems such as “Cypr*” (for variations of Cyprus in several languages), but those results typically included many names of persons (such as “Cyprianus”) or botanical names (e.g. “cypress) that distorted the overall output. At the same time, searches for very specific island names in just one language seemed to complicate the process.

Using island terms in different languages or island names as “subjects” (su:) retrieved lower results in comparison with “title” searches, and as keywords are not normalised, adding several spelling variants made a difference. The gap between “title” and “subject” results was greatest in French where the title search retrieved nearly seven times as many results. (ti:) and (su:) cannot be combined through “OR”, which is why combined searches in title and subject lower the result output. The comparative search output in national library catalogues was in most languages half-way between the WORLDCAT results for “title” and “subject” searches. It is unclear whether WORLDCAT includes more duplicates or if national library catalogues tend to miss out on items published or distributed “abroad”.

“Keyword” searches (kw:) retrieved 2.5 times as many results as “subject” searches, but here, too, the language was not normalised and adding the same keyword in different languages (e.g. English and Latin) increased the overall output. Also, “keyword” searches in WORLDCAT consider all fields including publication places and tend to retrieve more false negatives:

Keyword, kw:, coffee or tea and house+ [keyword searches: publication year, ISBN, geographic codes, map data, and all the information found in the Author, Title, Notes, Publisher, Publisher location, and Subject indexes]

Latin books entitled “de insulis” can only be found via direct title search as most Latin items in WORLDCAT do not have any keywords or tags at all. In general, missing metadata in the catalogues of the owning libraries influence the search results.

In order to capture as many relevant search results as possible, the following steps were taken:

a) Joint title search (ti:) for the word “island” in several languages with “OR”:

This is necessary because even a book using the Latin word “insula” could, in fact, be written in German, and because the trial searches have shown that even a Danish depiction of Riddarholm islet in the old town of Stockholm was captured by “title” searches in English and German. Filtering by individual languages would have excluded too many results in related languages or bilingual publications.

The Scandinavian languages had to be selected separately, though, because their island names could be read as invidual characters in words rather than words of their own. In addition, the Swedish National Library Catalogue” was manually searched for additional works.

Slawonic languages were widely absent in the first place and a check in the Polish national library catalogue revealed that most island works from the early modern period kept in Polish institutions are foreign language works.

Ottoman Turkish works from the Turkish National Library Catalogue turned out to be irrelevant for the research project.

*b) Merged title search (ti:) for (European) island names in several languages with “OR”

c) Subject search (su:) or keyword search (kw:) for names of non-European islands (in the language of their early modern colonizers)