Angkor
In the early days of Angkor, the worship of Vishnu was secondary to that of Shiva. The relationship seems to have changed with the construction of Angkor Wat by King Suryavarman II as his personal mausoleum at the beginning of the 12th century. The central religious image of Angkor Wat was an image of Vishnu, and an inscription identifies Suryavarman as "Paramavishnuloka," or "he who enters the heavenly world of Vishnu." Religious syncretism, however, remained thoroughgoing in Khmer society: the state religion of Shaivism was not necessarily abrogated by Suryavarman's turn to Vishnu, and the temple may well have housed a royal lingam. Furthermore, the turn to Vaishnavism did not abrogate the royal personality cult of Angkor. by which the reigning king was identified with the deity. According to Angkor scholar Georges Coedès, "Angkor Wat is, if you like, a vaishnavite sanctuary, but the Vishnu venerated there was not the ancient Hindu deity nor even one of the deity's traditional incarnations, but the king Suryavarman II posthumously identified with Vishnu, consubstantial with him, residing in a mausoleum decorated with the graceful figures of apsaras just like Vishnu in his celestial palace." Suryavarman proclaimed his identity with Vishnu, just as his predecessors had claimed consubstantiation with Shiva.
Wat Niwet Thammaprawat
The construction of Wat Niwet Thammaprawat was commissioned by King Chulalongkorn (Rama V) in 1876, to serve as the royal temple for the newly expanded Bang Pa-In Palace. The temple was designed by Joachim Grassi, one of the first Italian architects employed under the king's government. Many public buildings were built in the Western style during Chulalongkorn's reign, a trend reflecting the modernisation of Siam (as Thailand was then known) at the time. Wat Niwet Thammaprawat was built in Gothic Revival style, with stained glass windows and a Gothic altar. Its appearance resembles that of a Christian church, with the temple's main Buddha image in place of a Cross. Construction was completed in 1878.