How did Ash Wednesday become the first day of Lent?

Ash Wednesday became the first day of Lent through a combination of liturgical adjustments and the evolution of penitential practices.

Originally, the Lenten period varied in length. By the 7th century, four days were added to the existing six-week period to establish exactly 40 days of fasting, mirroring the time Jesus Christ spent fasting in the desert.1

The association with ashes stems from early church traditions in Rome. Penitents and those guilty of grievous sins began a period of public penance on the first day of Lent, during which they were sprinkled with ashes and wore sackcloth as signs of their need for reconciliation with the church. When these specific public penance rites fell into disuse between the 8th and 10th centuries, the practice of receiving ashes was extended to the entire congregation. This ritual serves as a *memento mori*, reminding all the faithful of their mortality and the necessity of repentance, thereby cementing the day's identity as Ash Wednesday.12