The Parish Church of St. John the Baptist (Biserica Romano-Catolică "Sf. Ioan Botezătorul") is the largest Roman Catholic church in the region. Its construction was sponsored by the Jesuits in the 18th century. The foundation stone was laid in 1728, the consecration took place in 1750, but the interior decoration was not completed until 1757.
The clearly structured, three-axis main façade is dominated by the two tall, Baroque spired towers. The most striking part of the interior is the monumental high altar, which occupies the entire sanctuary and was created in 1755 by two of the most talented artists of the century, Anton Schuchbauer and Johannes Nachtigall.
Târgu Mureș was purely Catholic in the Middle Ages but became Protestant in the mid-16th century during the Reformation. First, Lutheranism prevailed, followed soon by Reformedism (Calvinism). The churches, including the castle church, were given to the Reformed Church. Only a few Catholic families remained in the city. They could only live under restrictions; worship was not permitted.
In 1690, Transylvania lost its independence and became a Habsburg province. The new state supported the Roman Catholic Church. The parish church acquired its present form during the renovation from 1933 to 1935, when a small transept was added. This restoration was supported by the Romanian authorities to ensure that the surrounding buildings would appear immaculate for the consecration of the new Orthodox cathedral.