The live performances by the Grateful Dead at the Fillmore East are historically significant for several reasons:

1. Cultural Impact: The Fillmore East, located in New York City, was a key venue during the late 1960s and early 1970s, known for hosting some of the most influential bands of the era. The Grateful Dead's performances there contributed to the venue's reputation as a hub for counterculture and rock music.

2. Innovative Live Sound: The Grateful Dead were pioneers in live music performance, known for their improvisational style and extended jams. Their shows at the Fillmore East showcased their unique approach to live music, blending rock, folk, blues, and jazz influences, which helped to redefine concert experiences.

3. Historic Concerts: The Grateful Dead played several notable shows at the Fillmore East, particularly in 1970. Their performances during this time were characterized by a mix of original songs and covers, and they often included lengthy improvisational segments that became a hallmark of their live shows.

4. Community and Fan Culture: The Fillmore East concerts helped solidify the Grateful Dead's relationship with their fan base, known as "Deadheads." The communal experience of attending their concerts fostered a sense of belonging and loyalty among fans, which has persisted for decades.

5. Recording and Legacy: Many of the Grateful Dead's performances at the Fillmore East were recorded and have since been released as live albums, contributing to their legacy. These recordings capture the energy and spontaneity of their live shows, allowing new generations to experience their music.

6. Influence on Future Artists: The Grateful Dead's approach to live performance and their emphasis on improvisation have influenced countless musicians and bands across various genres. Their Fillmore East shows are often cited as examples of how to engage an audience through live music.

Overall, the Grateful Dead's performances at the Fillmore East are a significant part of rock history, representing a blend of musical innovation, cultural significance, and community building that continues to resonate today.