The third picture is of the Battle of Stirling Bridge in 1297, which was a major victory for Scotland in the First Scottish War of Independence. The English had to cross the River Forth to get to the Scottish Army, and the bridge was very narrow. The Bridge collapsed and a large amount of English soldiers died.
The fourth picture is of the Battle of Bannockburn, in 1314. It was a significant Scottish victory and secured Robert the Bruce's position as the King of Scots.
This song references Scotland surviving through difficult times, such as the Wars of Independence, Danish Vikings raids and the fact they didn't get conquered by Rome. It emphasises how Scotland has survived through all kinds of toil and strife.
