We’ve invaded Syria more than once over the centuries.
As early as the First Crusade, armed Englishmen seem to have been roaming Syria. When the army of the First Crusade turned up at the Syrian port of Latakia in 1097, after they had sweatily walked all the way across the Balkans and Turkey, they may have been somewhat surprised, and perhaps a little miffed, that an English fleet seemed to have got there first. Having said that, nobody now seems entirely sure what this English fleet was doing there, or who was in control of it. In a little-known fact of British history, after the Norman invasion of England substantial numbers of Anglo-Saxon exiles seem to have enlisted in the Emperor of Byzantiums’ Varangian Guard (a sort of French Foreign Legion of its day, or rather Byzantine Foreign Legion) and it has been argued that this English fleet was part of the force.
In the modern period, you would think our invasions of Syria would start with the Syrian War of 1839–40 in which we played such a large part. And it probably does, just about. Confusingly, the Syrian War (also called the Second Syrian war, or Egyptian-Ottomon War, or Second Egyptian-Ottoman war) saw extensive action on the land and in the waters of present-day Lebanon, Israel and Egypt, but not that much, or at least not that much involving us, in the area of present-day Syria. But since our ships’ operations seem to have extended all the way from Alexandria in Egypt to ‘Scanderoon’, the rather jolly English spelling of present-day Iskenderun in Turkey, it seems reasonable to assume that we were in Syrian waters at least at some point. There are no such questions over the British invasion of Syria in 1918 though. We were here, and here in force. After Allenby’s decisive victory over the Ottoman forces at the Battle of Megiddo (see Israel) on 19–21 September, his forces swept through Syria. Allenby’s troops, along with Lawrence and fighters of the Arab Revolt, entered Damascus at the beginning of October, with Lawrence in an open-top Rolls-Royce. Homs fell on 16 October and Aleppo was taken on 25 October. For a time after the war we maintained troops in Syria.
Eventually, the French were to take control of Syria under a League of Nations Mandate. Which meant that after the German invasion of France in 1940 and the creation of the Vichy French government, Syria in 1941 was a problem for us. Indeed, there were fears that German operations through Syria could undermine our position across the Middle East, particularly in Iraq.
On 8 June 1941, Operation Exporter went into action. British, Commonwealth and assorted other forces invaded Syria from the south, from what was then the Palestine Mandate. British and Commonwealth forces also invaded Syria from Iraq to the east. Despite a setback at Quneitra, and bitter fighting against often determined Vichy defenders, the force attacking from Palestine had taken Damascus by 21 June. Further north, the force attacking from Iraq took the fabulously historical city of Palmyra on 2 July. On 3 July, William ‘Bill’ Slim won the Battle of Deir ez-Zor and by 8 July, the 10th Indian Division was approaching Aleppo. An armistice was signed on 14 July.