Tianjin simply known as Jin is situated in the northeastern part
of North China Great Plain, bordering the Bohai Sea in the east,
leaning against the Yuanshan Mountain in the north, with its
terrain traversing the Haihe River through north and south. It has
become the hub of communications of North China and the gateway of
the capital city.
Tianjin was once part of Bohai Sea in the remote antiquity.
During the Pre-Qin days, Tianjin once belonged to the Yan and Qi
kingdoms of the Warring States. In the Western Han Dynasty, the
Tinajin region mainly was part of the Yuyang prefecture, Quanzhou
county, the Bohai prefecture and Zhangwu county.
The original name of Tianjin was "Zhigu". It was changed into
Tianjin in early Ming Dynasty. In 1398, Zhu Di dispatched troops
from Beijing in the pretext of "pacification of rebellion", and
defeated Zhu Yun Wen and became Emperor. In commemoration of the
place where he crossed the river moving southward, he renamed the
place "Tianjin" by imperial order, meaning "the place from where
the emperor crossed the river" and stationed "Tianjin Guards"
there. From then on Tianjin is also called "Tianjin Guards".
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Tianjin was built in the 2nd year (1404) of the reign of Emperor
Yong Le of the Ming Dynasty.
Tianjin was a seaport and an important gateway of the capital
city during the Qing Dynasty. The transport of grain by water to
the capital continued to develop and it became the economic center
in the north. (enorth.com.cn)