Trade wars in the past

 1.  Opium Wars

Trade wars in the past have sometime ended with actual military conflict.

The Opium Wars between the Qing dynasty and the British Empire in the mid-1800s.  This ended up forcing the Chinese to remove virtually all its onerous import duties as well as to give up Hong Kong to British rule.  By the time Hong Kong was returned to China in 1997, it was one of the most successful trading centers in the world.

2.  Banana Wars

The occurred between United States and several European countries at the end of the twentieth century.  These centered on removing European barriers to Latin American banana producers, which were mainly owned by U.S. companies.

3.  Pasta Wars 

In the mid-1980s, Reagan administration tried to open up markets for American lemons and walnuts in Europe by placing punitive tariffs on imports of European-made pasta.

Both the Banana and Pasta Wars disputes were resolved amicably with the warring parties gradually removing the disputed tariffs.