Moving from Scotland to Australia as a child, and to New Zealand as an adult, he rose from a working class shepherd, to sheep rancher and a rich land holder.

[1][2] Initially, the family was sustained by the large tracts of land they owned on the Isles of Tiree and Mull as well as on the mainland at Mowern and Ardnamurchan.

Allan McLean and his brothers John[3] and Robertson made a living as working class shepherds,[4] and became established enough so that they could buy two sheep runs in west Victoria, which they owned from 1848 to 1851.

[4] In 1852, the brothers purchased the Ashfield run adjacent to the Waimakariri River in Canterbury, New Zealand, and the family moved to that country.

[1] Robertson returned to Scotland but Allan and John owned runs in Canterbury, Otago, and Morven Hills, acquiring the Waikakahi property near Waimate from a Mr. Harris in 1866.

[2][11] Through his will, McLean made generous provisions for an institute that used his house "as a home for women of refinement and education in reduced or straitened circumstances".