What was the most likely reason for the protest? Catholic civil rights workers assembled in a city in Northern Ireland in 1972 for a protest. The protesters rallied in support of Irish nationalists.

The protesters were Catholic civil rights workers rallying in support of Irish nationalists, who generally opposed British rule in Northern Ireland and favored greater Irish self-government or unity with Ireland. So the most likely reason for the protest was to oppose British rule. Supporting British rule or Protestants would not match the stated support for Irish nationalists.

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