Jeremy Corbyn is absolutely right not to resign as Leader of the Labour Party. Those calling for his resignation – including those members of the Parliamentary Labour Party who supported the vote of no confidence against him – betray an astonishing misunderstanding of what the project called 'The Labour Party' is all about. Here’s the history lesson they all need to read, mark, learn and inwardly digest.

The project now called 'The Labour Party' owes its origin to a conference called in London in 1899 to discuss the palpable erosion of trade-union rights as a result of a succession of legal judgments. Out of that conference something called 'The Labour Representation Committee' was established (it changed its name to 'The Labour Party' in 1906). The purpose of the Labour Representation Committee (LRC) was to sponsor MPs who, once elected to Westminster, would be expected to promote and support legislation to reverse the cumulative effect of these legal judgments. The most radical of these judgments came in 1901, when, in the Taff Vale Railway case, the House of Lords awarded very substantial damages against the Amalgamated Society of Railway Servants, whose officials were held to have induced employees of the Railway to have breached their contracts of employment. In 1906 the Liberal government, supported by LRC-sponsored MPs, passed legislation that gave – and still gives – sweeping immunity to trade unions against all such civil claims.

So whereas the Liberal and Conservative parties began as groupings of MPs, and only later established extra-parliamentary mass-membership supporters’ clubs (the National Liberal Federation and the Conservative National Union), the Labour Party began as a mass-movement, and only later established a parliamentary party. This clearly posed – and apparently continues to pose – something of a challenge to British constitutional norms.

In 1909 Walter Osborne, a porter at Clapton railway station, won a legal action against his own union (the same ASRS), whose sponsorship of socialist MPs he strongly objected to. In that case the House of Lords expressed its horror that Labour MPs and parliamentary candidates should have been required to pledge themselves to (amongst other things) not support any candidate or MP not recognised by the Executive Council [now the National Executive Committee] of the Labour Party.

So who – actually – is in ultimate control of the Labour Party? There’s general agreement that Conference is, when it’s in session. Conference elects the NEC. Clement Attlee famously pushed back against the claim of NEC chairman Harold Laski that a Labour government was somehow subservient to the NEC ('a period of silence on your part' – Attlee wrote – 'would be welcome') but the fact of the matter is that the trade unions fund the party, and that she or he who pays the piper has a habit of demanding and being able to call the tune.

When the late John Smith abolished the trade-union bloc vote at Conference and replaced it with individual votes for each union delegate, pundits argued that this would weaken the influence of the unions. This has not happened. On the contrary, the reforms introduced into Labour’s constitution by Ed Miliband – allowing individual members of the public to take part in the leadership election on payment of a £3 fee (a move which received overwhelming endorsement by Conference) and decreeing that the Leader would be elected by 'one member one vote' – have actually strengthened the influence of affiliated unions over the leadership contest.

Jeremy Corbyn was, under this system, elected Leader of the Labour Party by almost 60 per cent of the party membership. Yesterday the general secretaries of ten of the country’s largest trade unions pledged their continued confidence in Corbyn as Leader. If Labour MPs find this state of affairs uncomfortable, it is always open to them to resign their parliamentary seats and fight by-elections on this issue. That would be an honourable way out. If they recoil from this prospect, a period of silence on their parts would be very welcome.

Geoffrey Alderman is Professor of Politics & Contemporary History at the University of Buckingham