Why was Jutland transliterated as 日德兰? Background: Jutland is the peninsula which makes up part of Denmark, and it was the site of the WWI Battle of Jutland (which is one of the main reasons "Jutland" would be written about at all in other languages). In Danish, it's pronounced ˈjylanˀ, and in German, it's pronounced ˈjyːtlant. That is, it starts with a "y" sound, and in German (the language of one of the participants of the battle), it retains the "t" sound as well.

Choice of 日?: So if it starts with a "y" sound, why was 日 chosen to transliterate the first syllable? In Mandarin, this is a poor fit. However, in Cantonese, it is pronouned jat6 (where "j" is, like in German, a "y" sound). This doesn't fully resolve the mystery though--the 德 in Cantonese is dak1, which is a worse fit than the Manadarin.

When was Jutland first written as 日德兰? What dialect was being used to make this transliteration?*
日 in Jyutping (Cantonese pinyin) is  [jat6] which sounds similar to 'Ju' in "Jutland"

德 in Jyutping is  [dak1]  which sounds similar to 'tl'  in "Jutland"

and 兰 is the common transliteration in both Cantonese and Mandarin