But Master Parslow managed to weave his ship back and forth across the North Atlantic, avoiding fire from the submarine.
He retreated to a bridge while his crew escaped but was killed by an enemy shell.
His son, also called Frederick, continued the battle to save his ship. Eventually he and the surviving crew, along with its cargo of 927 horses bound for the Western Front, were saved by two armed vessels.
Master Parslow, who was born in Balls Pond Road, was given a nominal rank of Lieutenant in the Navy Reserves so he could be awarded the Victoria Cross after his death.
A plaque was unveiled to honour his life on Islington Green today in an event organised by Islington Council, the Honourable Company of Master Mariners, the Merchant Navy Association and the Royal Navy.
Councillor Gary Poole, said: “Even though 100 years has elapsed since Master Parslow’s incredible act of bravery took place, it is fitting for us to pull out all the stops to remember him on this the 100 anniversary of his death.
“His was just one of countless brave deeds carried out by thousands of young men, many of which went unpraised. The paving stones are a way of cementing their memory for generations to come.”
The council said paving stones commemorating four more men from Islington who were awarded the Victoria Cross during the Great War would be unveiled over the next few years until 2018.
