... dazzlingly ambitious ... Abulafia never lets enthusiasm overpower him, knowing that goods often came hand-to-hand overland rather than by sea, and similarities between separated cultures may be 'processual' (arising independently out of circumstances) rather than the results of diffusion. But often the evidence astounds – like the coins of Augustus still in currency in 20th century Colombo ... Readers might reasonably anticipate dull determinism or boundless angst, but these shallows are avoided by shrewd sensitivity and the sheer majesty of [Abulafia's] subject. He sees inevitable – and desirable – cross-fertilisation where others see only one-way exploitation ... Atlantic histories often scant the pre-1492 period, but The Boundless Sea offers depth, zooming from ninth century steering to mirage-humped horizons ... reminds us brilliantly of once brand new landfalls, times when endless oceans glittered with primordial possibilities.

This is a book written with deep scholarship, but also with lightness and dexterity...with lyrical vibrancy ... It is the seamless melding of the personal and the universal that makes The Boundless Sea so compelling, as the reader meets explorers, brigands, religious fanatics and adventurers ... This book must be among the favourites of the year. It is rich, humorous and insightful, and Abulafia, emeritus professor of Mediterranean history at Cambridge, manages the art of letting his readers believe they are every bit as learned as he is for the happy days, or weeks, that reading this behemoth will take.

... seemingly insignificant 'facts' are subjected to rigorous analysis in this mammoth book. Cast aside what you think you know about maritime history ... This is a very long book because there are so many significant accomplishments to recount ... Abulafia is more interested in people than ships; there is little detail about actual vessels ... it’s difficult to find a geographical area that’s neglected. He also finds room for ephemera such as pirates, cruise ships and, of course, herring. I was repeatedly struck by just how much Abulafia knows ... a very long book packed with minute detail...Is this one too long? Perhaps. Abulafia occasionally reminds me of my uncle who told tales interesting only to himself. For the most part, however, this is a fascinating book that never descends into arcane theorising ... The material is neatly ordered and presented in fluent, accessible prose. Seafaring tales are told without opulent or contrived drama; what instead makes this book special is the sheer breadth of its coverage ... This book should not, however, be approached lightly. The reader will form a relationship with it that will last for weeks or perhaps months; it’s not a book for those who fear commitment. The Boundless Sea is best read slowly. Put it on the bedside table, read a chapter at a time and feast on the magnificent bounty that Abulafia has to offer.

If the story of this era leaves little room for new discoveries, the author is alive to the horrors of slavery and sectarian violence that accompanied the early European maritime encounters with African, Muslim and Amerindian societies in the Atlantic and Indian oceans. The period post-1750 of joint stock companies, the age of empire and the rise of steam is crammed into the final 150 pages in something of a blur — but it suits Abulafia’s longer historical trajectory, which forgoes an easy Eurocentric approach. Still, it remains alive to some remarkable and forgotten elements ... This hardly does justice to the richness and phenomenal detail that drive The Boundless Sea.

... astonishingly ambitious ... The author ranges fearlessly across time and space. His grasp of the material is not so much encyclopaedic as breathtaking, effortlessly moving from migration patterns across Polynesia to the archives of European trading companies of the early modern period...As one might expect from such a distinguished academic, extreme care is taken to note the difficulty of the evidence and to refrain from generalisations and simplified conclusions ... Despite the door-stopping size of the book, some topics are given strikingly little attention. The trans-Atlantic slave trade is barely discussed, for example, while the Royal Navy, its achievements, successes and occasional failures are only mentioned in passing ... Nevertheless, this is a tour de force. Writing history on this scale is challenging and enormously impressive; the author deserves applause for a magisterial achievement.

These pages feature the great sea-going nations of the past, the globe-circling commercial empires built on fragile ships and enormous risks, and Abulafia includes a colorful cast of mostly well-known figures along with equally important figures who will probably be less familiar to some readers ... Due to the sheer immensity of Abulafia’s subject – human interactions over centuries on three vast watery arenas – none of these figures can stay for long ... that’s one of the problems with a volume as big and inviting as this. Even while you’re floating along on the generous glories of its narrative, you’re noticing little bits and pieces that are missing. Far more notable, even given the page count here, is the sheer amount of detail Abulafia actually manages to include. Readers get glimpses of thousands of worlds ... through it all, Abulafia keeps one eye on the broader aspects of his subject, both the growing interconnectedness of his three separate water-worlds but also on the larger conceptions of what the oceans mean as spheres of human endeavor ... largely steers clear of those 21st-century questions, and it likewise doesn’t consider the rampant, worldwide damage humans are doing to these oceans.