1966 in the UK

3 January
British Rail begins full electric passenger train services over the West Coast Main Line from Euston to Manchester and Liverpool with 100 mph (160 km/h) operation from London to Rugby. Services officially inaugurated 18 April.
Stop-motion children’s television series Camberwick Green first shown on BBC1.
4 January – More than 4,000 people attend a memorial service at Westminster Abbey for the broadcaster Richard Dimbleby, who died last month aged 52.
12 January – Three British MPs visiting Rhodesia (Christopher Rowland, Jeremy Bray and David Ennals) are assaulted by supporters of Rhodesian Prime Minister Ian Smith.
20 January
The Queen commutes the death sentence on a black prisoner in Rhodesia, two months after its abolition in Britain.
Radio Caroline South pirate radio ship MV Mi Amigo runs aground on the beach at Frinton.
21 January – The Smith regime in Rhodesia rejects the Royal Prerogative commuting death sentences on two Africans.
30 January – Action Man toy action figure launched.
31 January – United Kingdom ceases all trade with Rhodesia.
9 February – A prototype Fast Reactor nuclear reactor opens at Dounreay on the north coast of Scotland.
17 February – Britain protests to South Africa over its supplying of petrol to Rhodesia.
19 February – Naval minister Christopher Mayhew resigns.
28 February – Harold Wilson calls a general election for 31 March, in hope of increasing his single-seat majority.
1 March – Chancellor of the Exchequer James Callaghan announces the decision to embrace decimalisation of the pound (which will be effected on 15 February 1971).
4 March
In an interview published in The Evening Standard, John Lennon of The Beatles comments, “We’re more popular than Jesus now”.
Britain recognized the new regime in Ghana.
5 March – BOAC Flight 911 crashes in severe clear-air turbulence over Mount Fuji soon after taking off from Tokyo International Airport in Japan, killing all 124 on board.
9 March – Ronnie, one of the Kray twins, shoots George Cornell (an associate of rivals The Richardson Gang) dead at The Blind Beggar pub in Whitechapel, east London, a crime for which he is finally convicted in 1969.
11 March – Chi-Chi, the London Zoo’s giant panda, is flown to Moscow for a union with An-An of the Moscow Zoo.
20 March – Theft of football’s FIFA World Cup Trophy whilst on exhibition in London.
23 March – Pope Paul VI and Michael Ramsey, the Archbishop of Canterbury, meet in Rome.
27 March – Pickles, a mongrel dog, finds the FIFA World Cup Trophy wrapped in newspaper in a south London garden.
30 March – Opinion polls show that the Labour government is on course to significantly increase its parliamentary majority in the general election tomorrow.
31 March – The Labour Party under Harold Wilson win the general election with a majority of 96 seats. At the 1964 election they had a majority of five but subsequent by-election defeats had led to that being reduced to just one seat before this election.[7] The Birmingham Edgbaston seat is retained for the Conservatives by Jill Knight in succession to Edith Pitt, the first time two women MPs have followed each other in the same constituency.

April – June