Green’s Dictionary of Slang

1. Belgravia, London [ext. of SE, i.e. the wealthy Jews who bought houses there].

2006

J. Ayto et al. Brewer’s Britain and Ireland 94: Belgravia [...] wealthy Jews earned it the slang nicknames ASIA MINOR, ‘the New Jerusalem’ and ‘Mesopotamia’.

2. Kensington and Bayswater, London [early use f. the large population of retired Indian civil servants; modern use refers to the Asian population, whether transient or immigrant].

1888		Daily News 9 Feb. 2/5: Notting-hill [...] is the centre of a district where Indians in the British metropolis mostly congregate [...] Asia Minor [as] it is sometimes called [F&H].
1890–1904		Farmer & Henley Sl. and Its Analogues.
2002		L. Pizzichini Dead Men’s Wages (2003) 121: In India, as well as in England, Bayswater is familiarly known as ‘Asia Minor’.