Reference

The crowd assembled at Albert Square the following evening for a variety of reasons, depending on the specific event in question. Here are some possible events based on historical records:

1. Peterloo Massacre Commemoration: Hundreds of people could have gathered at Albert Square to honor the memories and recreate in part the events of the Peterloo Massacre. This event commemorates a significant historical moment when a peaceful rally for political reform in 1819 turned violent source.

2. Manchester Attack Remembrance: Choirs led a mass sing-along at Albert Square to remember the victims of the Manchester attack. This event included a large gathering of people coming together in solidarity and remembrance source.

If you have a particular event in mind, please provide more details so that a more precise answer can be given.