The town was founded in 1827, but there were settlements in the vicinity as early as the 12th century. These tiny villages were built on small islands in the swampy estuary. There were early plans to found a fortified town on this site to protect ships leaving or entering the Weser River, and in 1672 Swedish colonists tried unsuccessfully to erect a castle (Carlsburg) there.
Finally, in 1827 the city of Bremen bought the territories at the mouth of the Weser from the Kingdom of Hanover. Bremen sought this territory in order to retain its share of Germany's overseas trade, which was threatened by the sedimentation of the Weser around the old inland port of Bremen. Bremerhaven was born and became a second harbour for Bremen, despite being 50 km downstream. Due to trade with and emigration to North America, the port and the town grew quickly.
The Kingdom of Hanover founded a rival town next to Bremerhaven and called it Geestemünde (1845). Both towns grew and established the three economic pillars of trade, shipbuilding and fishing. In 1927 Geestemünde and the neighbouring municipalities of Lehe and Wulsdorf were united to become the new city of Wesermünde, and in 1939 Bremerhaven was removed from the jurisdiction of Bremen and made a part of Wesermünde.
Bremerhaven was one of the important harbours of emigration in Europe.
As a key base of the Kriegsmarine, most of the city was destroyed in the Bombing of Bremen in World War II; however, key parts of the port were deliberately spared by the Allied forces to provide a usable harbour for supplying the Allies after the war. Bremerhaven was a postwar enclave run by the United States within the British zone of northern Germany. In 1947 the city became part of the Bundesland Bremen (Bremen Federal State) and was consequently renamed from Wesermünde to Bremerhaven. Today, Bremerhaven is therefore part of the state of Bremen, while also a city in its own right. This is complicated somewhat by the fact the city of Bremen has owned the "overseas port" of Bremerhaven since 1927. Further complicating matters, a treaty between the two cities (as mentioned in Section 8 of Bremerhaven's municipal constitution) makes Bremerhaven responsible for the municipal administration of those parts owned directly by Bremen (known as stadtbremisch).
The three roads connecting the city of Bremerhaven to the Autobahn 27 consequently are named after the original three twin cities:
Bremerhaven has only a few historical buildings, and the high street and city centre are almost exclusively post-war. The main attractions for tourists are the German Emigration Center (since August 8, 2005) and the German Maritime Museum (Deutsches Schiffahrtsmuseum) on the historical harbour with many museum ships, such as the Type XXI U-boat Wilhelm Bauer, the Seute Deern (a three-masted sailing vessel), and the Hansekogge, a vintage ship dating from 1380. The Lloyd-Werft shipyard is renowned for building and renovating large cruise liners, for example the Norway. The fishing port also houses an aquarium (the Atlanticum). The zoo reopened on 27 March 2004, after a lengthy renovation. It features Arctic wildlife, both terrestrial and marine. Attractions include the Klimahaus, simulating travel adventure along the 8th line of longitude.
The port of Bremerhaven is the sixteenth-largest container port in the world and the fourth-largest in Europe with of cargo handled in 2007. In addition, more than 1,350,000 cars are imported or exported every year via Bremerhaven. Bremerhaven imports and exports more cars than any other city in Europe except for Rotterdam, and this traffic is also growing.
The Fischtown Pinguins, also known as REV Bremerhaven, are a professional hockey team in Germany's 2nd Bundesliga league.