THE day before, Lady Londonderry was in Darlington, giving a speech to the local Conservative Association about the importance of midwives. The day after, Lord Londonderry was warmly welcomed at court in Durham as the new chief magistrate.

The days inbetween, the Londonderrys were at home at Wynyard Park, near Stockton, with their house guest Joachim von Ribbentrop, the German ambassador.

As this was November 1936, when the stormclouds gathering overhead must have blotted out the light, the four-day visit was controversial.

A new book, Making Friends With Hitler, tells how Charles Stewart Henry Vane-Tempest-Stewart, the 7th Marquess of Londonderry - "Charley" to the king - became besotted by the Nazis.

Londonderry, as befitted a man of his aristocratic breeding and of his experience as a Durham mineowner, was deeply suspicious of any left-wing politics. He believed Britain should befriend Hitler's Germany to stop communism creeping out of Russia and infecting Europe.

To this end, Londonderry visited Germany in December 1935 and February 1936. He went stag-hunting with Hermann Gring (Gring bagged a bison) and stayed for a week at Gring's luxurious mountain retreat at Berchtesgarten before going on to the Winter Olympics.

During his stay, he had a two-hour audience with Hitler, whom he found "forthcoming and agreeable".

Indeed, in a speech in Durham in March 1936, Londonderry described the Fhrer as "a kindly man with a receding chin and an impressive face".

In return for the hospitality, Londonderry invited Ribbentrop to a house party at Wynyard (Wynyard was the least favourite of Londonderry's five stately homes dotted around the British Isles).

"The high spot of the weekend," says Ian Kershaw in his new book, "was the grand ceremony of the Mayoral Service at Durham Cathedral."

Crowds thronged the streets hoping to catch a glimpse of the ambassador and his wife on their way to see Londonderry ceremonially installed as Durham's new mayor.

The Echo reports that in the cathedral Ribbentrop sat in the choir between the Bishop of Jarrow and Roger Lumley MP. "He took a deep interest in the impressive service," said the paper.

"At the end, the organist (Mr Conrad Eden) played the British and German national anthems."

What happened next, says Kershaw, was "a unique moment in the long annals of the venerable cathedral". For as Mr Eden began Deutschland, Deutschland ber alles, "Ribbentrop jumped to his feet, his outstretched arm in the 'Heil Hitler' salute".

Says Kershaw: "His arm had to be gently but swiftly lowered by the adjacent Lord Londonderry."

Both men were broken by the war that followed. Londonderry suffered a stroke but clung to life just long enough to see Ribbentrop convicted of war crimes at the Nuremberg trials and hanged - one of the most senior Nazis executed as most managed to kill themselves.

The Londonderry estate was also broken by the war. Wynyard was converted into a teacher training college, although Londonderry's son, Lord Castlereagh, maintained a wing as a private residence. The entire Wynyard estate was sold in 1987.

* Making Friends with Hitler: Lord Londonderry and Britain's Road to War by Ian Kershaw (Penguin, £20).