Book Review: Sea of Blood: A Military History of the Partisan Movement in Yugoslavia, 1941-45


by Gaj Trifkovic

Warwick, Eng.: Helion / Philadelphia: Casemate, 2021. Pp. xviii, 430. Maps, appends., notes, biblio., index. $59395 paper. ISBN: 1914059948

The Yugoslav Partisans

Stepping out of my comfort zone, I volunteered to review Gaj Trifkovic’s military study of the course of World War II in the former Yugoslavia. Perhaps I should not have been surprised to encounter a great many familiar themes. Like the I.R.A. during the Irish War for Independence (1919-21) and subsequent Civil War (1922-23), Tito’s partisans struggled with the difficulties of obtaining sufficient arms and ammunition, benefited from the invaluable support provided by friendly civilians (with consequences for such support at the hands of security forces), and encountered problems transitioning to a conventional military force, albeit all on a far larger scale in a vastly bloodier conflict.

Trifkovic has spent the better part of his life pursuing his interest in the horrific struggle that, from 1941 to the conclusion of the Second World War, laid waste to the former Yugoslavia. Having earned advanced degrees in the history of Southeastern Europe at Austria’s Karl-Franzens University, Trifkovic has written extensively on aspects of the war in this region, including his 2005 monograph Parleying with the Devil: Prisoner Exchange in Yugoslavia, 1941-1945. In Sea of Blood, Trifkovic takes on the daunting task of providing a narrative account that charts the fighting in the northwestern portion of the Balkans that was Yugoslavia. While his focus is on Josip Broz Tito’s partisans, Trifkovic gives us substantial and valuable coverage of the many different opponents against whom the partisans fought.

When in April, 1941, to his annoyance, Hitler felt compelled to invade Yugoslavia and Greece, the swift triumph of the Wehrmacht proved deceptive. No sooner had the Royal Yugoslav Armed Forces been destroyed than various groups began waging a guerrilla campaign that, over the course of four years, grew in scale and intensity. It’s tempting to envision a parallel between Napoleon’s ‘Bleeding Ulcer’ in Spain and the Third Reich’s war in Yugoslavia. As Trifkovic demonstrates, however, Germany was able to minimize the drain on its resources by relying heavily on its allies for occupation duties and counter-insurgency activities. This included a substantial commitment by Italy, and lesser contributions from Bulgaria and Hungry, all of whom were rewarded with pieces of the pie. In addition, there were the armed forces of the Axis-sponsored Nezavisna država Hrvastska (Independent State of Croatia), and a wide variety of locally raised units, including SS formations, that contributed, with varying degrees of effectiveness, to the struggle with the partisans. But, like the partisan movement itself, the Axis efforts were complicated by age old ethno-religious antagonisms. When the Serbian Chetniks, for example, chose to prioritize hatred of Communists over hatred of foreign occupiers, they joined the same side as Ante Pavelic’s State of Croatia, which was enthusiastically pursuing genocide against Serbians, as well as Jews and Gypsies.

Once Hitler launched Operation Barbarossa, Yugoslav Communists initiated their campaign of resistance. As was the case with Communist Parties throughout Europe, they already had the advantage of familiarity with covert activity due to their pre-war experience as an illegal organization. Trifkovic relates how their blind faith in Stalin and the Soviet Union convinced them that Hitler’s legions would be quickly smashed and their homeland liberated before the end of 1941! Regardless, the partisans began the long and costly process of trial and error. Units were formed throughout the country, recovering from defeats, building upon victories, and seeking to learn from both as an ever-expanding force of veteran guerrillas.

According to Trifkovic, 1943 was perhaps the most challenging year for Tito’s partisans. Hitler feared that, as the war in North Africa was coming to a conclusion, the Allies might choose the Balkans as their next theater of operations, in which case the pacification of Yugoslavia was vital for the defense of the Third Reich’s southern flank. Large scale encirclement campaigns were initiated that inflicted heavy casualties on the partisans, but ultimately failed to eradicate them. The subsequent recovery of Tito’s forces was, to some degree, facilitated by the Italian armistice, which resulted in a windfall of arms and equipment.

Trifkovic draws a contrast between the assistance provided by Great Britain and the Soviet Union. Churchill initially supported Yugoslavia’s Royal Government-in-exile until the Royalist guerrilla forces, the Chetniks, began aiding the Axis in its battle against the partisans . The British gradually began supplying Tito with a wide variety of aid which included, not only arms and ammunition, but such vital necessities as food, shoes, and medical care. Seriously wounded partisans, for instance, were transported across the Adriatic to military hospitals in liberated Italy. Allied warplanes flown from bases in Southern Italy provided Tito’s forces with invaluable air support at a time when Axis aircraft had all but disappeared from the skies above the Balkans. By the end of 1944 Soviet forces were advancing into the region and were able to link up with the partisans. In contrast to the British, whose relations with Tito were always, to one degree or another, tentative (increasingly so as the war drew to an end), the Russians were more than happy to shower aid upon fellow heroes of the Proletariat. Nevertheless, the elimination of the remaining Axis forces in Yugoslavia was largely left to the partisans supported by their former enemy, the Bulgarians. This was due to a combination of circumstances, including problems with declining Soviet manpower and the fact that Stalin’s primary goal was the invasion of Germany.

Sea of Blood is nothing short of a triumph of research. As Trifkovic explains in his introduction, the partisan movement and Tito’s postwar government produced an immense number of primary documents. One collection alone, albeit the most ambitious, consists of 173 bound volumes published between 1949 and 1986. Because of the combination of difficulty of access and language barriers, they’ve remained largely untouched by Western scholars, which is exactly what makes Sea of Blood so valuable to English speaking readers. Throughout his book the author notes instances of politically motivated bias within these documents and seeks to correct the record. Trifkovic also relies on a wide range of non-Yugoslavian sources, particularly surviving German reports, along with a multitude of secondary sources in a variety of languages.

Ironically, Trifkovic’s exhaustive account of the innumerable operations conducted by the partisans, both great and small, presents its own problems. Up until the arrival of Soviet armies in late 1944, Tito’s forces fought as insurgents, and guerrilla warfare, by its nature, is decentralized, composed of a ‘thousand separate cuts’ inflicted on the enemy. Despite the author’s efforts to provide color to distinguish the different units and their activities, too often the narrative descends into an exhausting list of actions that numbs the reader.

A key contributing factor to this problem concerns the issue of cartography. A general rule of thumb to which I myself have tried to adhere is that if a location is mentioned in an author’s text, then, as a courtesy to the reader, it should appear on any accompanying maps. Although the publisher, Helion, was generous enough to include fourteen maps, less than ten percent of the locations mentioned by Trifkovic can be found on them. While this speaks well of the author’s attention to detail in his narrative, one either must have a large, comprehensive map of the former Yugoslavia unfolded next to him / her while wading through Sea of Blood or hope that Trifkovic and Helion produce an accompanying atlas.

Though of lesser concern, Trifkovic’s over reliance on acronyms – 167 by my count – also contributes to the readers' difficulties. Using terms such as C.O.I.N. and O.K.W. are one thing, but does P.R. for Police Regiment or I.D. for Infantry Division really save that much space? I found myself continually flipping back and forth between the chapter I was perusing and the long list of abbreviations at the front of the book in order to determine the meaning of, for instance, B.D.O., G.V.D., M.V.A.C., and R.S.S.C. (Commander of Order Police, Group of Air Divisions, Voluntary Anti-Communist Militia, and Railway Security Staff Croatia, respectively).

That being said, these are mere petty complaints, vastly outweighed by Trifkovic’s remarkable achievement. The result of an astounding amount of diligent research based on a massive collection of primary sources little explored by western historians, Sea of Blood is by far the most important English language book about the military history of Yugoslavia during World War II to be written up until this time. While it is not for the casual reader, Sea of Blood is indispensable for any scholar seeking to understand the course of the Second World War in the Balkans.


Our Reviewer: Paul V. Walsh earned his Master’s degree in Military and Diplomatic History from Temple University in 1994 and taught history at Delaware County Community College from 1999 to 2009. His most recent article, “Italians on World War I’s Western Front.”, appearing in Issue No. 334 (May-June, 2022) of the magazine Strategy & Tactics. He has previously reviewed for us Arming the Irish Revolution: Gunrunning and Arms Smuggling', 1911-1922




StrategyPage reviews are published in cooperation with The New York Military Affairs Symposium

Reviewer: Paul V. Walsh   

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