Green’s Dictionary of Slang

(Anglo-Ind.) a morning on which one sleeps in or rises late.

1879		Viscount Hinchingbrook Diary in Ceylon & India 150: Not having got to bed till nearly 4 a.m., I took what in India is called a European morning, i.e., did not get up till 9 a.m.
1885		Vanity Fair (London) 33 108/1: The next morning (being a ‘Europe morning’ – an Indian idiom which signifies ‘nothing to do and plenty of time to do it ‘in’’) a long-drawn hullaballoo, followed and accompanied by heartrending shrieks, at the door of the Senior Subaltern’s house.
1889		H.G. Blackwood Our Viceregal Life in India 284: I took a ‘European morning’ after having had three days of going out before breakfast, and read and wrote all the day.
1895		C.S. Cumberland Sport on the Pamirs 47: In spite of the promise of what in India is called a ‘Europe morning’ – i.e., getting up late – I awoke at daylight and soon turned out.
1904		Highland Light Infantry Chron. Apr. 59/1: To-night is our turn for outpost duty, so this morning I gave the Battalion a morning ‘in,’ what in India we used to call ‘a Europe morning’; reveille an hour later than usual, and no parade before breakfast.
1906		Civil & Milit. Gaz. (Lahore) 14 Feb. 4/1: On Wednesday a Europe morning was kindly provided by the authorities.
1915		Queenslander (Brisbane) 4 Dec. 17/4: On New Year’s Day (1913) we had a ‘Europe morning,’ and did not get up till long after sunrise.