Commonwealth Civil Registration Start Dates
From 1st July 1837, the registration of Births, Deaths and Marriages in England and Wales became the responsibility of the state, (although this wasn't compulsory until 1874). However, it took a while for the rest of the UK and Commonwealth to follow suit.
So far, I have found dates for the begining of civil registration for the following:
Australia
1838 Tasmania
1841 Western Australia
1842 South Australia
1842 Victoria
1856 New South Wales
1856 Queensland
1870 Northern Territory - Births only
1872 Northern Territory - Deaths and Marriages
1930 Australian Capital Territory
Canada
1864 Nova Scotia - doesn't cover Births and Deaths between 1876 and 1908
1869 Ontario
1870 North West Terriorries
1872 British Columbia
1878 Saskatchewan
1882 Manitoba
1888 New Brunswick
1891 Newfoundland
1897 Alberta
1898 Yukon
1906 Prince Edward Island
1926 Qubec
Isle of Man
1849 Births and Marriages - voluntary
1878 Births and Deaths - compulsory
1884 Marriages - compulsory
Jersey
1842 Births, Deaths and Marriages
New Zealand
1848 All Births, Deaths and Marriages - voluntary
1856 Births, Deaths and Marriages of Europeans - compulsory
1911 Marriages of Maoris - compulsory
1913 Births and Deaths of Maoris - compulsory
Scotland
1855 Births, Deaths and Marriages
South Africa
1820 Cape of Good Hope - Marriages (incomplete)
1895 Cape of Good Hope - All Births, Deaths and Marriages
1868 Natal
1901 Transvaal
1902 Orange Free State
1923 All Births, Deaths and Marriages for the whole of South Africa
N. B. Before 1923 records are held in provincial archives, after this date they are held centrally by the Department of Home Affairs.