I was asked for a definition of Lascar and realise I got the answer wrong.   They were Indian sailors who were employed on ships travelling out to Asia and back, particularly by the East India Company, although their numbers were restricted by the Navigation Acts and there were anxieties about the numbers of them in London which led to the Committee for the Relief of the Black Poor in 1786, intended to help lascars as well as ex-slaves.   Large numbers of them came to London in the late nineteenth century which is why they figure so prominently in the literature of the east end.