Arquivo F1785 - Canada West. Provincial Secretary's Office fonds

At the union of Upper and Lower Canada in 1841, the division of responsibilities between the offices of Civil Secretary and of Provincial Secretary and registrar was clarified, confirming an evolutionary trend. Where the Civil Secretary had been the principal channel of communication for the government before the Union, after 1841 the Provincial Secretary's office was the focus. This evolution in the bureaucracy paralleled and reflected the development of responsible government in the political arena.

While the office of the Civil Secretary to the Governor was unified in 1841, that of the Provincial Secretary and Registrar continued a separation based on geography. The old territory of Lower Canada was now termed Canada East and the old Upper Canada, Canada West. Parallel record-keeping systems were established by the Provincial Secretaries, using a numbered file registry system.