Wat Arun, วัดอรุณ, or more completely Wat Arunratchawararam Ratchaworahawihan, วัดอรุณราชวราราม ราชวรมหาวิหาร, is a
first class royal temple that was built at the end of the Ayutthaya period.
It was first called Wat Makok and then was changed to Wat Makok Nok
because there was another new temple in the area called Wat Makok Nai (Wat
Nualnoradit). At a later date, King Narasin the Great brought in
troops via the river (Chao Phyra) and reached the temple at early dawn.
This inspired him to renovate the temple and he renamed it to Wat Chaeng,
meaning the Temple of the Dawn. When the new capital was founded at
Thonburi in 1768, the King built a new palace around the temple. Wat
Chaeng was the royal temple of Thonburi without monks in residence.
At one time, the temple held the Emerald Buddha and Phra Bang which were
brought from Vientiane during the reign of King Rama I. When the
capital and the royal palace were moved to Bangkok, the palace wall was
taken down. Thus Wat Chaeng was no longer the royal temple in the
palace and monks were allowed to reside there. Renovation of the
temple continued during the reign of King Rama II who changed the name to
Wat Arun Ratchatharam. It was again renovated by King Rama IV who
renamed it Wat Arun Ratchawararam.