Liberty poles can be considered to be the predecessors to our flagpoles.
The first pole was actually a tree located in Concord, MA used as a
meeting place for the Sons of Liberty and other pre-Revolutionary War
patriots.
Flagstaffs or poles were erected in the tree to indicate
meetings or protests. The symbol of a pole with a flag of protest spread
throughout the colonies and became known as Liberty Poles, which were
used by the colonists to protest British Colonial laws and taxations.
The flags flown were often ensigns which were red signifying protest.
The symbolism was further developed to include a pine tree which had
become synonymous with liberty, freedom, independence and strength.