Casey’s Irish Pub opened its doors in 1971, when the surrounding area was coming of age as Downtown Los Angeles’s modern-day Financial District. Casey's was designed to resemble a turn-of-the-20th-century Irish pub, and initially catered to nearby working professionals in search of respite, a light meal, and libation, after work. Today, it draws a diverse and loyal clientele, especially for its hugely popular annual St. Patrick's Day Street Festival, the largest of its kind in Los Angeles.

In 2020, Casey's St. Patrick's Day Festival was set to take place off Grand Avenue and at Union Station's Imperial Hardware for the first time in eleven years. Due to COVID-19 and public health concerns, the event has been cancelled.