Born in Clifton, Yorkshire, England, on 27 October 1826, Firth was the son of a reverend and headmaster whose family had interests in farming, with investments in the wool trade.

After a brief period in Victoria and New South Wales, he moved onto New Zealand and settled in Auckland, establishing a business making bricks.

Time and the natural progress of events will, nevertheless, shortly either enforce the prescription and exact the fee, or consign the refractory patients to a swift and sure destruction.

"[2] In Auckland he was one of a small group of highly influential business men such as John Logan Campbell, Frederick Whitaker and Thomas Morrin.

In 1865 with the establishment of peace in the Waikato, Firth was able to lease land from Tamihana of Ngati Haua, a kingitanga tribe.

Firth noted that although Te Kooti was unarmed he was backed by a semi circle of heavily armed men with modern weapons in good condition.

The Premier, Willian Fox, and the government agent for Hawkes Bay, John Davies Ormond, were irate "with that meddlesome sweep Firth."

In 1873, Firth began a seven-year project to clear the Waihou River of snags and obstacles to navigation thus opening the upper reaches of the Thames Estuary to shipping.

To the rear of the wooden Gothic house he erected a large wing in the castellated style which included a 15-metre (49 ft) tall tower, completed in 1873.

As a member of the Beresford Street Congregationalist Church in Karangahape Road, Firth influenced the choice of concrete for that building as well (1875).

Firth had played a part in the establishment of Tāwhiao's father, the Waikato chief Pōtatau Te Wherowhero, as the first Māori King in 1858.

Later he began to develop a trade in pumice based on its properties of insulation and fire resistance, travelling to the United States and England.

He died suddenly on 11 December 1897 just as the venture was becoming successful,[1] and was buried at St Stephen's Cemetery in the Auckland suburb of Parnell.