From the mid-1800s, Scotland experienced a steady fall in its population - immigration into the country was lower than the number of people leaving the country.
Towns and cities grew as people moved from rural areas and abroad to Scotland's 'central belt' looking for factory work.
This had a negative impact on living conditions and created competition for jobs. Overcrowding in Scotland’s cities became a major problem.
Irish and Canadian people fought with the Scots in the battlefields of World War One, where many friendships were formed.
Indian and Australian people also made a key contribution to victory in the war.