Stories of the now iconic Windrush are usually told as if this was solely a voyage of Caribbean economic migrants, but actually among hundreds of white people aboard was the famous writer, black rights activist and disinherited shipping heir Nancy Cunard (1896-1965).

Anorexic wild child Nancy had, since the 1920s, mixed with key black activists and artists such as US singer Paul Robeson and Trinidadian George Padmore, the editor of the Negro Worker.

Although they were in or close to the Communist Party, Nancy herself never joined. It’s joked that she couldn’t take the discipline.

However she proclaimed: “It is communism alone which throws down the barriers of race as it finally wipes out class distinctions.”

A researcher-traveller, she’d become bored at her cousin Edward’s house in Glitter Bay, Barbados aka “Little England.” News of last minute cut-price tickets galvanised her.

She wasn’t sailing on this particular ship to make a point or common cause on a new sort of Mayflower, which it wasn’t. It was just a handy way to get home from Trinidad to the UK.

Stage one of the trip via Jamaica, Bermuda, Cuba and Mexico began when she boarded Windrush in “evil-smelling” Port of Spain on May 19 1948, waiting suffocatingly in port for three days.

Calling into struggling Jamaica, by May 24 the ship was joined by 500-plus Caribbean women and men desperate for a new life in the UK, unlike Nancy. Indeed, she deplored what was called the Negro self-betterment movement, taking the Communist line that it was counter-productive to gaining real justice.

It is communism alone which throws down the barriers of race as it finally wipes out class distinctions

The big group of young male hopefuls was travelling deck class in no-frills dormitories. They were five decks down from the top deck where this still famous 52-year-old lover of black men was loathing the Brits and not socialising much.

One way the two worlds met was in supporting Evelyn Wauchope, when the female stowaway was discovered a few days out.

In Cunard mythology it was Nancy who collected among the passengers and raised the £43 fare plus pocket money so that the 25-year-old hairdresser and war widow wouldn’t be imprisoned on arrival. The rescue story fits with Nancy championing of the Scottsboro boys in 1932.

But actually, in Jamaica’s Kingston Gleaner, a student correspondent credited boxing manager Mortimer Martin and Delroy Stevens’s calypso singers for arranging a benefit concert to raise the required money — the equivalent of about nine months wages for a banana loader or a hundred days of an RAF aircraft hand sergeant’s pay in the war).

According to a letter home from travel writer Freya Stark, with whom Nancy shared a cabin, the ship was “desolatingly efficient” with megaphones blaring and military regimentation.

By May 31, Day 13, Stark wrote: “It really is sordid. It is a godsend to have Nancy Cunard. We omit breakfast and lie with very little on in our cabin till lunch and then sit in hot shade with typewriter …. Heat … as bad as Delhi last night, the sheets scorching; and poor miserable people are down below in decks that descend to E without a breath of outside air.”

Meanwhile panicky messages were being exchanged between local diplomats, the Colonial Office and the ship — all these men arriving, without skills or survival money. Would it mean trouble?

Nancy was preparing notes for her new book about Mexico, which never transpired. Maybe this is the reason for there being no record of any protesting from her at what seems to be passengers breaching labour solidarity in Bermuda’s naval base, c June 10.

The Gleaner’s student correspondent wrote innocently: “Due to a dock strike, provisions were loaded with the help of the troop-deck civilian workers.”

After 33 days, on June 22, the would-be settlers landed. “Reporters swarmed the boat … Almost every paper had sent a man to get a story about the ‘Windrush.’ Indignation was felt when someone referred to the job-seekers as ‘refugees.’ They felt that that was an insult. They were all British subjects, in fact,” said the student correspondent.

Stark was met at St Pancras by her publisher’s car and whisked away to the grandly shabby Cafe Royal for Barsac, then to an Elizabeth Arden session — not with her cabin-mate.

EL Melbourne, a Kingston passenger, had been concerned when Nancy “expressed her desire to employ the [stowaway] girl in France as a maid … in my opinion if it became necessary for her to leave Miss Cunard’s employment she may have found herself in a worse plight in France than she could find herself in England, where there are welfare officers to give her assistance.”

Melbourne was right. Nancy turned out to be homeless for months afterwards, living with a colony of hard-drinking literary expats such as Malcolm Lowry in Giverny.

By contrast, Wauchope landed on her feet at the Colonial Girls’ Hostel in Collingham Gardens, Earls Court. She managed to get a job at £4 per week.

Eight days later, 145 of the 492 male settlers had jobs. None of them could have known that they’d be faced with the current struggle to have their citizens’ rights respected 70 years on.