Well, kiddo, amalgamation is when two or more things come together to become one big thing. Like when you mix different colored paints to create a new color or when you put two puzzles together to make a bigger puzzle.
In history, amalgamation usually refers to when two or more countries decide to join together and become one big country. This has happened many times throughout history, and it can happen for lots of different reasons. Sometimes it's because the countries are all part of the same region and have similar cultures and languages, so they want to work together more closely. Other times, it's because the countries are struggling on their own and think that they would be stronger if they combined forces.
For example, in the 1800s, the British North American colonies (which are now Canada) decided to amalgamate and become one country. They did this because they thought they would be safer and more prosperous if they worked together, rather than staying as separate colonies.
Amalgamation can be a really big deal, because it means that the different parts of the new country have to figure out how to work together and share power. This can be tricky, and sometimes it can take a long time for everyone to agree on how things should be done.
So that's what amalgamation means, buddy! It's when things come together to become bigger and stronger.