Following her arrest, Marsh, who represented the Stray, Woodlands and Hookstone ward as a councillor in Harrogate, resigned from her post after three decades in public life.
She was also suspended by her party, the Liberal Democrats.
She had denied the posts were antisemitic prior to being charged.
Prosecutor Ashleigh Metcalfe had told the court most of the content which Marsh posted on X while a serving councillor was “concerned with the events in Gaza and was plainly anti-Israel”, adding: “Some of it was antisemitic.”
“We say it’s greater than bigotry in the extreme,” she said.
The posts attracted hundreds of views, said Metcalfe, who told jurors they were later picked up by local and national media outlets, thereby expanding their reach.
Eric Watson, defending Marsh, accepted evidence proved the posts existed and were capable of being seen, but suggested this “does not by itself prove who published them”.
The jury of nine men and three women concluded Marsh posted or distributed written online material likely to stir up racial hatred.
