In 1852, at the age of 17, he moved to Manchester, England, where his maternal uncle operated a shipping office.

In 1857 he followed his brothers, Isaac and Michaelis, to Daylesford in the Victorian goldfields, Australia.

They were wed in the Anglican parish church in Alford, Lincolnshire, on 14 February 1861.

[4] Hallenstein's son-in-law (and nephew) Willi Fels was a prominent philanthropist and arts collector in early Dunedin.

Hallenstein's great-grandson Charles Brasch was a noted poet, literary editor and arts patron.