The explorations of James Cook and George Vancouver, and the concessions of Spain in 1794 established British claims over the coastal area north of California.

Meanwhile, the mainland continued to function under the de facto administration of the HBC, whose chief executive, James Douglas, was also governor of Vancouver Island.

Almost overnight, some ten to twenty thousand men moved into the region around present-day Yale, British Columbia, sparking the Fraser Canyon Gold Rush.

To normalize its jurisdiction, and undercut any HBC claims to the resource wealth of the mainland, the district was converted to a Crown colony on 2 August 1858 by the Parliament of the United Kingdom, and given the name British Columbia.

Magistrates and constables were hired, mining regulations drawn up, and town sites surveyed at Yale, Hope and Fort Langley to discourage squatting on crown land.

The rush indeed was short lived, and the exodus of miners, speculators, and merchants was already underway by the time the Royal Engineers had laid out the colony's new capital at New Westminster.

Provisioning was already proving to be an acute problem, and with more distant finds it became clear that wagon trains would have to replace pack horses, necessitating new infrastructure.

[6][7] When news of the Fraser Canyon Gold Rush reached London, Sir Edward Bulwer-Lytton, Secretary of State for the Colonies, requested that the War Office recommend a field officer who was "a man of good judgement possessing a knowledge of mankind" to lead a Corps of 150 (later increased to 172) Royal Engineers who had been selected for their "superior discipline and intelligence".

[5] Moody had hoped to begin immediately the foundation of a capital city, but on his arrival at Fort Langley, he learned of an insurrection, at the settlement of Hill's Bar, by a notorious outlaw, Ned McGowan, and some restive gold miners.

He founded the new capital city, New Westminster,[5][19] at a site of dense forest of Douglas pine[19] that he selected for its strategic excellence including the quality of its port.

[18] He, in his letter to his friend Arthur Blackwood of the Colonial Office that is dated 1 February 1859, described the majestic beauty of the site:[20][12] "The entrance to the Frazer is very striking--Extending miles to the right & left are low marsh lands (apparently of very rich qualities) & yet fr the Background of Superb Mountains- Swiss in outline, dark in woods, grandly towering into the clouds there is a sublimity that deeply impresses you.

[...] My imagination converted the silent marshes into Cuyp-like pictures of horses and cattle lazily fattening in rich meadows in a glowing sunset.

[...] The water of the deep clear Frazer was of a glassy stillness, not a ripple before us, except when a fish rose to the surface or broods of wild ducks fluttered away".

[25] Throughout his tenure in British Columbia, Moody feuded with Sir James Douglas, Governor of Vancouver Island, whose jurisdiction overlapped with his own.

Governor Douglas's ethnicity was 'an affront to Victorian society',[27] whereas Mary Moody was a member of the Hawks industrial dynasty and of the Boyd merchant banking family.

[8] Scott contends that the dissolution of the Columbia Detachment, and the consequent departure of Moody, 'doomed' the development of the settlement and the realisation of Lord Lytton's dream.

The creation of an assembly and Seymour's appointment in April 1864 signalled a new era for the colony, now out of the shadow of Vancouver Island and free of a governor suspicious of sharing power with elected representatives.

Douglas's wagon road project was still underway, presenting huge engineering challenges, as it made its way up the narrow Fraser Canyon.

Successive loans authorised by Seymour's predecessor, largely for the purpose of completing the road, had put the colony £200,000 in debt; and the Chilcotin War of 1864 cost an additional £18,000 to suppress.

Seymour himself made the difficult journey through the Great Canyon of the Homathko and Rainbow Range as a show of force and participation in the hunt for Klatsassin, the Tsilhqot'in war leader, but the armed expedition reached a denouement when Klatsassin surrendered on terms of amnesty in times of war, only to be tried and hanged for murder, as Seymour had not endorsed the terms.

Seymour opposed this proposal, but with pressure from various quarters of the colonial government, he eventually relented, recommending that British Columbia be the dominant partner, and (unsuccessfully) that the capital be located at New Westminster.