Strange how a mere piece of cloth can evoke such fierce emotion. Just think of the nun’s veil, Jewish tallit, Palestinian keffiyah, Muslim hijab or, more prosaically, an Arsenal scarf. Nothing, however, stirs passion quite like flags. For many, they do indeed seem to be worth dying for, as the title of Tim Marshall’s book affirms.

At first glance, the subject might seem dry, but Marshall has drawn on 25 years as a reporter in 40 countries to produce an engagingly written, veritable page-turner. Whether the topic is ethnic identity, Japanese imperialism, Panamanian shipping law or the defeat of Nazism, flags speak volumes about our human condition.

First on parade is America’s star-spangled Old Glory, revered at home yet often reviled abroad. Its nemesis, the Confederacy flag, explains Marshall, variously symbolised states’ rights, the Klan and the good old South.

Last year, South Carolina removed it from state-house grounds after a racist murder. And, of course, BNP bigots once nearly hijacked the Union Jack, notes Marshall; since then, Brits of all hues have reclaimed it, memorably the great black athlete Mo Farah.

But, hints Marshall, the neglected Welsh dragon will slip in if Scots leave Brexit Britain and take their Cross of St Andrew with them.

One-sixth of the world’s national flags use Christian imagery, although fewer Europeans attend church and Western flags first arrived from China via the Arabs. Likewise post-Soviet central Asia has seen Islamic crescents combined with far older motifs oust the hammer and sickle.

The birth of new nations has spawned fresh flags on every continent — and the departure of old ones. Marshall recalls 1980 in Rhodesia, soon to become Zimbabwe, when the Union Jack “dropped all the way into the African dust” with unmistakable symbolism. In 1994, when South Africa jettisoned apartheid emblems, Fred Brownell was asked to devise a new flag after 7,000 alternative designs had been rejected.

However, Nelson Mandela received a black-and-white fax of Brownell’s design for final approval, so aides had to buy crayons at a local store and fill in the all-important colours. Happily, Fred’s Rainbow Nation ensign passed muster!

For its part, Israel chose the biblical Star of David set against a backdrop suggestive of a tallit. But it almost was the menorah, Marshall reveals.

Many Middle Eastern flags use the template of the 1916 Arab Revolt banner — paradoxically designed by British colonial Svengali, Mark Sykes. The purest instance of this is the Palestinian flag.

The question remains, who owns the Palestinian flag — the PLO or the Palestinian people? Palestinian academic Dr Mahdi Abdul Hadi argued against a former Israeli ban on the flag saying it was not the sole property of Arafat’s movement. That led him to admit that the PLO has no flag of its own.

By contrast, the PLO’s main group Fatah does have its own banner. And here the contradictions begin. The group formally supports a two-state solution, notes Marshall, yet displays a map of “all-Palestine”. It officially foreswore the armed struggle in 1993 but maintains the unnerving image of two interlocked Kalashnikovs; and while Fatah is ostensibly secular, the Fatah-affiliated Al Aqsa Martyrs Brigade prominently displays on its banner the Dome of the Rock mosque from Jerusalem’s Temple Mount.

So why not remove or alter them? To do so, suggests Marshall, would alienate sections of Palestinian society who would simply transfer loyalty to Hamas or others. One might add, if mischievously, that borderless territory appears on Israeli maps too; and at least Fatah, Hamas and Hizbollah have localised aims, whereas proto-Daesh proclaimed as early as 2007 that its black banner become “the sole flag for all Muslims”.

Worth Dying For concludes with a survey of transnational banners from the Jolly Roger and the Red Cross to the notional International Flag of Planet Earth. The latter seems a distant dream. As to why nationalism remains so buoyant, in Bob Dylan’s words and with Marshall’s book to hand, well, “the answer is blowing in the wind”.

Lawrence Joffe is the author of ‘An Illustrated History of the Jewish People’