The Union between Sweden and Norway was established in 1814 after the Napoleonic Wars. It was a political agreement that aimed to unite the two countries under a single monarch while allowing them to maintain separate laws and governments. The union was formed when Norway was ceded to Sweden by Denmark in the Treaty of Kiel. Despite the initial cooperation, tensions grew over time due to differences in national identity and governance. The union officially ended in 1905 when Norway peacefully declared independence, leading to the establishment of a separate monarchy and the recognition of Norway as an independent nation.