It is believed that Protase was beheaded in Milan about the year 165.
Saint Protase, along with his brother Saint Gervase, was executed during the persecution of Christians under the Roman Emperor Nero in the 1st century. They were martyred for their faith and refusal to renounce Christianity. Their deaths are commemorated in the Christian tradition as a testament to their steadfast belief.
Protasius (Protase) is considered a Christian Martyr, possibly beheaded, circa 165 AD, according to Catholic tradition, during the reign of Marcus Aurelius. Note that the Catholic Church had not officially been started until after Constantine's Edict of Milan in 313 AD. Some deny their existence, and make them a Catholicism legend of the the Dioscouri, meaning the "Sons of Zeus," mythical characters. Not too much else is actually known about Protasius outside the traditions of the Roman Church.
There are a number of saints who were siblings. Here are a few: St. Scholastica and St. Benedict St. Gervase and Protase St. Cosmas and Damian St. Begga and St. Gertrude
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