Charles Courtenay Lloyd, who loved books and languages and married the Russian princess he first kissed in the library at 'spy school', died on Monday at the age of 102.
His daughter Masha Lloyd said he was one of the last surviving veterans to have fought for peace in Europe, as she paid tribute to the "remarkable journey" of a man who "lived life to the full".
"He was a true English gentleman," said Ms Lloyd. "He was one of so few left to tell the tale, and now he no longer can.
"He always said he wasn't a hero. He was so humble, but he meant everything. Losing him is the end of an era, they don't make them like that anymore."
A naval veteran in the Second World War, Mr Lloyd, known as Courtenay, was awarded a medal from the King of Norway for his outstanding contribution to the country's liberation.
Stationed in Oslo with officers supervising the surrender of German forces, he went on to become an intelligence officer tasked with dismantling the Nazi regime and catching war criminals.
He came from a "genteel" time, said Ms Lloyd, unprepared for life at sea. That first night as an able seaman he had unpacked his pyjamas, she chuckled, and got down on his knees to pray.
"That was his nature all his life," she said. "It was how he was brought up I suppose. He was a good man. If he knew about all these tributes flooding in, he would ask what the fuss was about."
An Old Cliftonian and graduate of Selwyn College Cambridge, Mr Lloyd's first job was teaching Russian to future spies at what the KGB called 'spy school'.
It was here that he met and fell in love with a penniless Russian Princess, Her Serene Highness, Elena Von Lieven, whose family had fled the revolution.
Their first kiss, said his daughter, was in the library, as was apt as they both loved books.
Born the son of a clergyman in Staffordshire in 1919, he was a polyglot, fascinated by languages and words, and is also remembered as an "inspirational" languages teacher.
'Old Boys' tributes
This week, as flags were flown at half mast at Bradford Grammar School where he taught from 1964 to 1983, Ms Lloyd said she was deeply touched by a flood of tributes from Old Boys.
One, former head of BBC News Roger Mosey, now Master of Selwyn College, said his had been a life "spectacularly well lived", bringing learning and wisdom to so many.
In class, Mr Lloyd is said to have "come into his own", described as passionate and somewhat eccentric, but who passed on his knowledge to make his lessons "unforgettable".
At home, said Ms Lloyd, he was more modest, and would likely now be amazed at the fuss.
He was the father who cooked "teas", she recalled, which were nearly always burnt sausages, and would do the hoovering with his apron on while listening to the rugby on the radio.
He was never happier than when walking on Ilkley Moor, she added, or listening to weather reports and "foreign stations" on his short wave radios.
His hidden pleasure had been sweet treats, she added in an eulogy to be read today, with a stash of goodies hidden in his desk to be consumed while marking students' homework, while he "adored" the school puddings.
A memorial service is to be held today in Madrid, where Mr Lloyd had lived with his daughter in later life, close to his grandchildren and great-grandchildren.
It was his wish for his ashes to be beside those of his wife in Baildon, and the family hope to have a "proper send off" in Bradford when travel allows.
As a boy, said Ms Lloyd, her father had a picture of a fawn above his bed with the words 'be a good beast, suffer in silence'.
"That was his motto all his life," she said yesterday. "I was by his side at the very end. His last words to me were 'I'm all right, thanks to you'. He always said that.
"In a humble way, he reminded me of Captain Tom Moore, whose biography I bought him last Christmas. They were so similar, from the same generation."
To mark her father's 100th birthday Masha Lloyd published The Biography of C. Courtenay Lloyd, where more can be discovered about his remarkable life.
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