[2] A family conference consisting all the above plus Ann Taylor (née Macfarlane) and her husband decided that they would answer to the advertisements for tradesmen and women to emigrate to New Zealand.

[1][2][3] Henderson and his brother-in-law John Macfarlane entered into a professional partnership in 1842, beginning by selling general merchandise and goods for ships.

[4] The Henderson & Macfarlane business later grew to include kauri timber milling and shipping, under the name Pacific Island Traders (later known as the Circular Saw Line).

[4] In 1844, Henderson & Macfarlane purchased 18,000 acres of West Auckland from Ngāti Whātua in return for goods and a schooner, the Lucy Dunn, however the government voided the land sale shortly after, when it was decreed that all purchases of Māori land needed to be done through the central government.

[8] During the Flagstaff War, he employed about 300 Māori in gumdigging and was credited by other colonists as keeping them from joining Hōne Heke.

[9] The Henderson & Macfarlane company continued to develop; by the year 1865, the Circular Saw Line fleet had 39 vessels.

[17] At the instance of Sir George Grey, who at the time was Premier, he was appointed to the Legislative Council on 25 July 1878 and served until his death in 1886.

Around the same time, Walter Brodie imported English pheasants (Phasianus colchicus) and released them near Mongonui.

[1] His body was transferred to Auckland on the SS Penguin and buried in Symonds Street Cemetery beside his wife.

All central Henderson streets were once named after members of the family (e.g. Thomas, Henry, John, Mary and George), but they have either been renamed or removed.