Even the most casual visitor to Prague senses the melancholy that seeps from its very stones. The beauty of the city intensifies the sadness. Czech history is embodied in monuments and grand facades, each of which stands as a sooty record of some invasion, rebellion, or internecine conflict. In their stark simplicity the memorials to the Hussites seem somehow antiphonal to the hectoring porticos of Counter-Reformation churches and the triumphal palaces of the Habsburgs. And yet, out of the cacophony of monuments, each with its fierce claim on remembrance, an uneasy coherence has taken shape, making of Prague not only one of the loveliest cities of Europe but a place whose golden aura is invariably tinged with shadow. Prague’s splendor, like its beer, comes with a bite.

Of course, given their history, especially in the century just past, Czechs have every reason to be mistrustful of any grandiosity not peppered with skepticism. Landlocked, hemmed in by powerful and aggressive neighbors, the “Czech Lands” have served for centuries as a stomping ground for those with imperial and territorial ambitions. Under the visionary presidency of the philosopher and statesman Thomas Garrigue Masaryk, Czechs did enjoy a brilliant republic from 1918 to 1938. But then came six years of Nazi occupation in all its barbarism followed by decades of equally brutal Soviet domination. Now, almost 70 years later, with access to official records and freedom to re-examine the past, Czech history – like that of Poles or Russians or Hungarians – can be seen not as some abstract pattern of national tragedy but as the sum total of millions of individual tragedies, each of which possesses its own distinctive and unforgettable voice.

When that voice belongs to a mother or a father, the process of unearthing the past must be nearly unbearable, a kind of slow exhumation of memory validated by layers of recovered documents. If carried through unflinchingly, and without sentimentality, the result can give back life, as well as some measure of justice, to the dead. In “Reflections of Prague: Journeys through the 20th Century” (Wiley, 318 pages, $24.95), Ivan Margolius accomplishes this difficult task with a rare combination of pathos and objectivity. Mr. Margolius, a Prague-born architect and architectural historian long resident in London, has sought not merely to uncover the facts of his father’s show trial and execution in 1952, but to recapture the brisk and vibrant personality of the man himself, and of the various worlds – political, artistic, familial – that he inhabited. Along the way he creates a vivid picture of Prague, and especially Jewish Prague, during some of the worst years of its long history.

The bare facts are terrible enough. Mr. Margolius’s father, Rudolf Margolius, survived Auschwitz and Dachau to become deputy minister of foreign trade from 1949 to 1952 in the Communist government. Blinded by his own idealism, he worked tirelessly for the new regime but was swept up in the Soviet-instigated purge that led to the notorious Slansky trials. (The grotesque machinery of these bogus tribunals will be familiar from the Costa-Gavras film “The Confession,” based on the 1973 book by Artur London, one of the three defendants not executed.) Under prolonged duress, Rudolf Margolius, along with Slansky and 12 others, not only confessed falsely to treason but made abject public statements of self-condemnation and was sentenced to death. All, not coincidentally,were Jews. Despite international outrage, these innocent men were hanged on December 3, 1952, by executioners working in nonstop shifts. After cremation, the ashes of the victims were scattered on the wintry Bohemian highways as road-salt.

Mr. Margolius was 5 years old when his father vanished.Almost a decade passed before he learned the truth. Now, half a century later, like some skillful restorer assembling a damaged portrait from scattered shards, he has patiently put together salvaged letters, old photographs, archival documents, and tattered memorabilia to set against the heartless transcripts of his father’s interrogation and trial. His own childhood recollections quicken the portrait; we seem to glimpse Rudolf Margolius in his snappy fedora turning a corner or picking up his long-suffering violin to play Dvoryak’s “Romance.”

There’s something almost mythic in Mr. Margolius’s stubborn quest. Like some latter-day Telemachus, he searches for a father who can never be found again. But to accomplish this, he also must reconstruct the Prague of his parents, as if there he might catch some splintered reflection of their lives. Kafka, Max Brod, and Franz Werfel, poets and composers and intellectuals, impinge on his father’s world. In evoking the intricate relationships that characterized Jewish Prague – the bonds of marriage and kinship, the friendships, alliances, betrayals, and liaisons – he gives a palpable sense of the milieu in which his father once drew breath.

When we come to the dreadful transcripts of the trial and to the letter his father wrote him on the eve of his execution (but which he didn’t see until many years later), we feel that a world, as well as an individual, have been placed in the dock and condemned. In the letter, Rudolf Margolius tells his son, “I have grievously offended society and was justly condemned for it,” and he exhorts him to “condemn me harshly.” This is a letter that Josef K. might have penned but all the more horrible for being real.

In 1986, Mr. Margolius’s mother, Heda Margolius Kovaly, published “Under a Cruel Star,” her own account of the same ghastly events. Her story remains a classic tale of survival against all odds and is as remarkable for its hard-won serenity as for its unsparing truthfulness. Her son has had a harder task. If his book lacks the terrifying immediacy of that first-person account, it is also more reflective and more nuanced. She made the trip out of hell, he’s chosen to revisit it. Small wonder the golden memorials of Prague are veined by shadows; they are the marks of tears.

eormsby@nysun.com