For thousands of years Syria has been one of the most strategically important regions on Earth. Dan Snow visits Roman temples, the centre of the world’s greatest Islamic empire, crusader castles and today’s battlegrounds to piece together the complex history of a country at the heart of the Middle East. To understand what's happening in Syria and this region at the moment, there's only one place to start, and that's in the past. In an hour-long documentary for BBC Two’s This World, Dan finds that the influence of history has been complicating Syria’s civil war. What started as peaceful protests against President Bashar al-Assad’s totalitarian regime have turned increasingly into a struggle along sectarian lines fuelled by historic tensions, involving global and regional powers. From the historic split between Sunni and Shia Islam, the divide-and-rule tactics of the French colonial rulers, and the struggle between secular and religious political parties, Syria’s history is a living and crucial element of the war. Dan meets those fighting on both sides of the conflict and hears grievances stretching back centuries. He also spends time with ordinary Syrians who are bearing the brunt of the casualties. They’re asking what the future for them and their country, which has often borne the brunt of history, now holds.