“Mandarin” also being the name of a particular type of orange (fruit) because of the Chinese connection. The Dutch word for the fruit being “sinaasappel” — Modification of earlier “Chinas-appel” (close enough to English to guess) — https://en.m.wiktionary.org/wiki/sinaasappel

However, the Orange Order in Northern Ireland is named after the Dutch King William of Orange, whose title “Prince of Orange” derives from a principality in southern France — https://en.m.wikipedia.org/wiki/Prince_of_Orange — but this in turn is probably etymologically derived from the Gaulish ar-aus(i)o- ('temple, cheek': https://en.m.wikipedia.org/wiki/Orange,_Vaucluse) while the fruit and colour come from the Arabic nāranj (نارنج) which is probably close to the original name for the fruit in Asia.