THIS IS A BOOK with a curious history. The author was a friend of Evelyn Waugh and Randolph Churchill, who made a literary career out of writing biographies of 20th-century British notables, like his father F. E. Smith and scientist Frederick Alexander Lindemann. At the end of World War II he met Captain George Bambridge, the husband of kipling's heir, proposed to write the life of Kipling too, and was accepted. He was given free access to the Kipling papers, which no investigator had seen, and every sort of cooperation. But when he finished his work, and sent the manuscrpit to Mrs. Bambridge, in 1948, she forbade him to publish it. (They had signed a contract giving her that right at the beginning of the project.) Only now that she is dead, which is when he too is dead, can the book appear.

Now there are not-as you might suppose-any startling revelations or speculations here. The Kipling papers probably don't include material for anything like that. The Kiplings were very cautions; the writer himself destroyed a lot of family papers; and his own letters, even to close friends, were written in a bluff style which revealed little of private thoughts or feelings. Nor does the book make any severe judgments on Kipling's art. Lord Birkenhead was interested in the man not the work, and his interest was not judgmental.

So why this outrageous censorship? Lord Birkenhead himself, and his son Robin, who introduces the book, cannot explain it. What Mrs. Bambridge said was that he did not make enough of Kipling's love of the countryside, and a few other flimsy pretexts. But she also said that Birkenhead was "allied to the Bright Young Things"; that is, to those amoral revellers fo London in the '20s whom we read about in the novels of Evelyn Waugh. And though Robin Birkenhead dismisses this too as "tryly ludicrous," I will suggest that that was her motive and that it was in its way reasonable.

Of course, there were no Bright Young Things in 1945, but in their heyday Birkenhead's friends, Waugh and Churchill, and his own sister Eleanor Smith, had been leaders; and they were deeply hostile to Kipling. Kipling was the greatest national symbol of what they rebelled against, the bard of that patriotism which had led to the disasters of 1914. From Kipling's point of view, they were betraying England, which he already saw as threatened by Germany. He thundered against them, and they giggled against him.

During World War II, however, they were (at least, Waugh, Churchill, and Birkenhead were) reconciled to patriotism, war, and the Kipling virtues.

Many of them were Consevative candidates of Parliament in 1945, on the strength of their good war records. Thus, one can well understand why Mrs. Bambridge would entrust the biography to Birkenhead in 1945. But by 1948 the memory of that moment of reconciliation had faded. Forty-eight was the time of George Orwell's literary ascendancy, and Orwell must have been, in Mrs. Bambridge's eyes, Kiplings's worst enemy. If you let your mind dwell on the dates, the story becomes comprehensible.

Of course, Mrs. Bambridge's part is still eccentric, in the loose sense paranoid, but that too is comprehensible in the light of her family tradition. For three generations that family had maintained a defensive and suspicious exclusiveness against the rest of the world which imposed a great strain on the individual members. Rudyard's parents spoke of the "family square" they composed with their two children, and the square was military. But they, Alice and Lockwood, were attractive and high-spirited people, with lots of friends. Rudyard and his wife Caroline formed a much grimmer and more nerve-wracked pair, in later years unhappy with each other. And Elsie Kipling Bambridge seems to have been even more possessed by suspicions and resentments. Of course, she was the guardian of a treasure-the Kipling papers and all they stood for-a treasure the outside world wanted both to rifle and to desecrate.

For three generations the Kiplings had been nay-sayers-even at the height of Rudyard's success, he was defending himself on all sides - and Elsie's was a bitter heritage. Some of the photographs of father, mother, and daughter in the '20 show a caricature of the English family-so dowdy, so grim-faced, so unhappily locked together-making mutual duty compensate for all it cost them. It was that family style which the Bright Young Things mocked as much as Kipling's politics-his antifeminism, anti-Boshevism, and his calls for war-preparedness.

As for the book's contents, they reward reading if you take any interest in Kipling as a figure in history. It is neither well nor badly written. (Lord Birkenhead was not a man of strong mind.) But there is a lot of fresh detail here about the second half of Kipling's life after he returned to England from India and found himself a famous author while still a very young man.The London Times devoted a leader to his work in 1890, and from then on he was acknowledged as the Bard of Empire. Poems like "Recessional" were printed in The Times and taken as such solemn pronouncements that Kipling was not even paid for them.

Lord Birkenhead tells us a lot about Kipling's political opinions and activities and his relations with men of power in government, industry and opinion-making. Kipling was both a personal friend and a political ally to Lord Beaverbrook (Max Aitken), who came to dominate the British newspaper world, to Stanley Baldwin, who was prime minister in the '30s, to the chairman of British Cunard, to Alfred Milner, the proconsul of South Africa, and so on. He actually wrote official speeches for Cecil Rhodes, the king, and the prime minister.

Here we have a man of letters who separated himself from the party of literature and joined the opposite side, the party of power. Moreover, because of his extraordinary success, and extraordinary gifts, he was welcomed and made much of by that party. We cannot, today, make a hero of Kipling, the man of politics (though he was right at certain moments when everyone else in literature thought he was wrong). But we can see him as a unique and tragic and endlessly interesting case. CAPTION: Picture, Rudyard Kipling