Kazhdan was born in Moscow in 1922. In 1944 he married Musya Ivanskaya, who did feel the cold but became the model of a dissident's wife. The poor eyesight which saved Alexander Kazhdan from call-up to the Great Fatherland War was later to threaten drivers on the Washington Beltway. Instead he enrolled with E.A. Kosminsky, the historian of medieval England, who drafted Kazhdan into Byzantine Studies, then being revived as an oblique part of the national search for the Russian Fatherland.
But from 1946 until well after Stalin's death in 1953 the highway to academic preferment was blocked. The families of Alexander and Musya Kazhdan were tainted: not just as bourgeois, but Jewish - by race rather than religion: among Kazhdan's earliest publications are texts on atheism, which perhaps aroused his awareness of Byzantium as a politically Orthodox state. In Stalinist terminology the Kazhdans were "rootless cosmopolitans". Rootless they were not, but Alexander Kazhdan made the accusation of "cosmopolitan" a virtue. From his academic exile in teachers' training colleges in Tula or Velikye Luki, scholars in the West incautious enough to write on Byzantium began to receive crabby letters, to which Kazhdan expected a reply.
From 1956 he was back in Moscow. The Kazhdans' tiny apartment shrank his files to scale: their format was the size of a large postage stamp, which he could pocket to take to the libraries: necessity imposed a pointilliste approach, with a passion for order and categorisation which brought him close to Byzantines such as the 12th- century historian Niketas Choniates, noting how he used every word. These cards, at which Kazhdan squinted on the Moscow Metro, were classified not just by their subjects' thought, word and deed, but by heads, bodies and legs. The intellectual scale was cosmic, adding up to a "homo Byzantinus". Like Kosminsky, Kazhdan began with the peasant, moving on to works on culture (in 1968) and the ruling class (1974).
By 1976 the climate had still not thawed. The emigration of the Kazhdans' son David to the United States did not help and in Moscow the Khrushchevite young guard just became old under Brezhnev. Zaina Udaltsova, Kazhdan's departmental head at the Historical Institute of the Soviet Academy, is now perhaps best remembered for her attempts to pin the awkward giant down. There were pinpricks. In 1976 I arranged to meet Kazhdan at last in Moscow to collaborate on a session of the International Byzantine Congress. The usual channels produced the wrong Kazhdan (a psychiatrist), so we wolfed the caviare which Intourist offered in silence. The real Kazhdan did not show up for the congress in Athens either: Udaltsova said he was ill.
By 1979 Kazhdan had become an unperson. Soviet scholars found ingenious ways to refer to his books, which they could no longer find in libraries. For Kazhdan, outspoken in favour of public discussion, this was the last straw. Somehow his precious files turned up in diplomatic shoeboxes in Vienna and there was relief in Moscow when Musya and Alexander arrived without passports in Paris.
Still without identity, they were allowed passage to the Centre for Byzantine Studies in Birmingham University. There he lectured like Gladstone: full measure. To us it was no shock. In Russia he had been a window on the West, an interpreter of the French Annales School, then already running its course. Was he now going to be a window on the East? But what most shocked Kazhdan, in February 1979, was that we did not know how to deal with snow in Birmingham. Scornful, he climbed straight up on to the roof of my house to send it down.
Kazhdan spent the remainder of his life at Dumbarton Oaks, Harvard University's Byzantine research outstation in Washington, which is a bosky swimming pool attached to an incomparable library in a house with echoes of Stravinsky where, if he had wished, Kazhdan could have ordered filing cards the size of bedsheets. He did not. His own cards held the matter of three great books: People and Power, with Giles Constable (1982); Literature, with Simon Franklin (1984); and Change, with Ann Epstein (1990); and finally his edition of The Oxford Dictionary of Byzantium (1991), a massive undertaking which he had first mooted in the 1940s.
Dumbarton Oaks had perhaps expected to exhibit a giant from the East, but some were unnerved by Kazhdan's candour which was as absolute as his own self-confidence. To younger scholars, especially, this combination was irresistible. In turn, Kazhdan was perhaps most disconcerted by the way individuals chopped up his subject in the West; he goaded younger ones to collaborate on his grand projects. Perhaps Dumbarton Oaks was too soft a bed. Kazhdan offered academic beds which became harder the closer one got to him. Musya bottled berries for the bruised.
Kazhdan was not a great frequenter of the Cosmopolitan Club in Washington. He preferred breakneck rambles to the Potomac Falls. Could the new generation of students keep up with him? Certainly they hung on to his wry wit as much as those he had taken mushrooming in the Moscow woods, where his roots ran deepest.
Gladstone, another candidly confident giant, wished to die in church, somehow without disturbing others. Kazhdan died by the swimming pool at Dumbarton Oaks. He might have chosen the place, and his wish to disturb Byzantinists still abed will be seen to by his students.
Alexander Petrovich Kazhdan, Byzantine historian; born Moscow 3 September 1922; married 1944 Rimma (Musya) Ivanskaya (one son); died Dumbarton Oaks, Washington DC 29 May 1997.