Edward VIII falls in love with a Black Londoner, (obviously his fascist sympathies would have to be butterflied away), instead of Wallis Simpson. This relationship is viewed with as much controversy as the OTL relationship with the American divorcée.
Following his accession to the throne, like his OTL counterpart, he refuses to sacrifice his relationship for political reasons, and he abdicates after only a few weeks. A year later, their first child, Victor, is born.
His brother George succeeds him as king, and takes the UK through WWII.
George VI dies in 1950, and his eldest surviving daughter, Margaret succeeds him, proving to be an adequate, but unremarkable monarch. Margaret's offspring grow up in the spotlight and turn out to be quite a scandalsome bunch. Meanwhile, Victor Windsor is considered increasingly popular, especially in the press.
The 70s and 80s roll on and many of the same social and racial problems of OTL occur. But Victor Windsor and his young family prove to be a vital bridge between the establishment and the disenfranchised lower classes.
In 1988, Margaret I dies, and is succeeded by her son George, widely considered to be a bitter and misanthropic drunk.
In 1994, after years of political isolation, a radical Labour government comes into power. After a few years, it becomes clear that George VII fails at his duty to remain apolitical, as leakages to the press show him to be increasingly at odds with the policies and personalities of the Labour government.
In 1996, Victor Windsor dies, and the British public grieves publically. In a deadly blow to his credibility, George VII appears to be unmoved by the death of his relative.
In 1997, George VII is assassinated while on a state visit to Australia. The issue of succession comes to the fore, as none of the king's siblings or offspring are viewed to be acceptable in the political climate. Meanwhile, several major historians now argue that Edward VIII's adbication so many decades ago was in fact constitutionally illegitimate - this view holds sway with many on the centre left, and so, an act of parliament is passed, appointing Victor Windsor Jr as Britain's new king.
King Victor I, at the time of his coronation is divorced, (from a White British woman), and has one daughter from that marriage.
In the year 2000, Victor I announces his engagement to a prominent social campaigner from the Confederation of the West Indies, a Black woman.
In 2028, Victor I dies and is succeeded by Queen Anne, the product of his first marriage (who is one eighth Black). Queen Anne herself dies in 2035, and is succeeded by her half sister, Maria, (who is five eighths Black).