Answer
In the late 19th century, Siam was faced with the threat of being colonized by the European powers. To avoid this, Chulalongkorn made territorial concessions to the British and French. In 1855, he signed the Bowring Treaty with the British, which gave them free trade rights in Siam and limited the power of the king. In 1893, he signed the Franco-Siamese Treaty, which ceded several provinces to the French.