Amoy was the original name of Xiamen due to the language spoken there. The people of south Fujian and Taiwan speak Hokkien, a dialect that is still widely spoken, although Mandarin is the common language for business and schools today.
The coastal cities of Fujian, including Quanzhou (today a city of over 7 million that you've likely never heard of), were extremely active port cities. Quanzhou was China's busiest port in the Tang Dynasty. Marco Polo remarked on its vast trade in his travel memoir.
Xiamen was a busy seaport starting in the Song Dynasty. Later, It became an outpost and refuge for Ming loyalists fighting the Manchu Qing Dynasty. Koxinga, son of a merchant pirate set up his anti-Qing base in the area and today a large statue in his honor looks out over the harbor from Gulang Yu island.
Arrival of Europeans:
Portuguese missionaries arrived in the 16th century but were quickly kicked out. Later British and Dutch traders stopped in until the port was closed to trade in the 18th century. It wasn't until the First Opium War and the Treaty of Nanking in 1842 that Xiamen was re-opened to the outside when it was established as one of the Treaty Ports open to foreign tradesmen. At that time most of the tea that left China was shipped out of Xiamen. Gulang Yu was allotted to the foreigners and the whole island off Xiamen became a foreign enclave. Most of the original architecture remains. Stroll down the streets today and you can easily imagine you are in Europe.
The Japanese, World War II and post-1949:
The Japanese occupied the area (they were in Taiwan, then Formosa since 1895) from 1938 to 1945. After the Japanese were defeated by the Allies, and China came under Communist control, Xiamen became a backwater. Chiang Kai-Shek took the Kuomintang and most of China’s national treasures across the Strait to Taiwan and so Xiamen became the frontline against an attack from the KMT. The PRC didn’t develop the area for fear of any development or industry being attacked. Taiwan’s Jinmen Island, just a few kilometers off the coast of Xiamen, became one of the most heavily armed islands in the world as Taiwanese feared attack from the mainland.
After Deng Xiaoping’s led Reform and Opening, Xiamen was reborn. It was one of the first Special Economic Zones in China and received heavy investment not only from the mainland but also from businesses from Taiwan and Hong Kong. As tensions decreased with Taiwan, Xiamen became a haven for businesses coming to the mainland.
Today Xiamen is seen by Chinese as one of the most livable cities. The air is clean (by Chinese standards) and people there enjoy a relatively high standard of living. It has large swathes of green space and the coastline has been developed for recreation – not only beach play but also long stretches of jogging paths, rare in Chinese cities.