1. In 1681, on March 21, King Charles II of England granted a charter to William Penn, thereby establishing the colony of Pennsylvania. Penn envisioned Pennsylvania as a place of religious tolerance and political freedom, and his legacy is still felt today.

2. In 1806, on March 21, the Pennsylvania Legislature enacted the Public School Law, also known as the Free School Act. This law required every township in the state to establish and maintain a public school, and it was a major step forward in providing education for all children in Pennsylvania.

3. In 1861, on March 21, the first shots of the American Civil War were fired in Pennsylvania. Confederate forces under General Stonewall Jackson attacked a Union outpost at Harpers Ferry, West Virginia, which was then part of Virginia. The attack was repulsed, but it marked the beginning of the bloodiest conflict in American history.

4. In 1911, on March 21, the Triangle Shirtwaist Factory in New York City, which employed many Pennsylvania residents, caught fire and killed 146 workers, most of them young immigrant women. This tragedy led to major reforms in workplace safety and labor laws, and it remains a powerful symbol of the struggle for workers' rights.

5. In 1963, on March 21, the Equal Pay Act was introduced in the United States Congress, with Pennsylvania Senator Hugh Scott as one of its co-sponsors. The act aimed to eliminate wage disparities based on gender, but it took many more years of activism and advocacy to achieve real progress in this area. Today, Pennsylvania is still grappling with issues of equal pay and workplace equity, but the spirit of progress and reform that characterized these events of March 21 continues to inspire us all.