Pope Sixtus IV inaugurated the Sistine Chapel’s first public Mass in 1483.
The chapel was consecrated and dedicated on 15 August 1483, the Feast of the Assumption. Sixtus IV celebrated the first Mass there, marking the completion of the initial building and consecration phase. The chapel takes its name from this pope, whose Latin name was Sixtus.
This event occurred before the famous Renaissance ceiling and altar-wall decoration. The early chapel already contained wall frescoes by artists including Perugino, Botticelli, Ghirlandaio and Rosselli, while Michelangelo’s major commissions came decades later.
Sixtus IV should not be confused with Julius II. Julius commissioned Michelangelo’s ceiling in the early sixteenth century, whereas Sixtus IV established the chapel itself and presided over its first public liturgy.