Toronto-born, London-based historian Ignatieff (A Just Measure of Pain, The Needs of Strangers) is descended from Russian counts, princesses, generals, and diplomats. Here, in an informal, meditative family-history, he recounts the lives of his grandfather (minister to Czar Nicholas II) and grandmother--based largely on their unpublished memoirs. Grandpa Paul was the anxious, sickly son of Count Nicholas Ignatieff--a celebrated diplomat of the 1870's, a notorious Minister of the Interior (masterminding repression) in the 1880's, a bitter has-been by the 1890's. . .and an awesome, suffocating father. In 1903, Paul married shy Princess Natasha Meschersky (who was raised on a huge country estate) after a one-month courtship; this ""blind throw"" in the matrimony gamble led to some 40 years of incompatability and idiosyncratic devotion. Natasha endured pleasureless sex, nonstop childbirth, and infant mortality while Paul rose to become Minister of Education--urging liberal reforms on the Czar, trying ""to salvage what was honourable from what was reactionary"" in the old traditions, staying on in this tortured ministerial role till 1916. Then, however, when the family fled from Petrograd to the Caucasus, where the shattered Paul was arrested and very nearly executed, it was Natasha (along with an English nanny) whose angry energy kept the Ignatieffs together till they settled in 1919 England. The rich narrative and character potential in this material--including hints of offbeat love-triangles (Paul's infidelities) and other family-saga elements--remains largely undeveloped in Ignatieff's brisk, sometimes sketchy, strictly factual narration. (He admits that he was tempted towards historical fiction.) More satisfying are the detailed evocations of country/city households. And though an opening chapter strains hard to evoke the ambivalent nature of roots-seeking, the book becomes immediate and affecting only in the closing pages, when the author describes a recent visit to each of his old uncles. Less successful than other attempts at blending personal and family history, then, but intermittently fascinating for devotees of aristocrat-Ã‰migrÃ‰ literature.