"He was portrayed as a villain because he had ordered to drive faster, get on a lifeboat, and save his own life.
"Ismay never recovered from the disaster and entered a spiral of depression from which he never recovered.
"The telegram he wrote to his valet's assistants was undoubtedly shaped by guilt and genuine compassion."
MHarrison of Wallasey, Cheshire, died along with over 1,500 others in the disaster.
The body of the 45-year-old was recovered from the water days later and buried in Halifax.
His last possessions, which he had recovered from his body, were sent back to his widow.
They have now been discovered by a direct descendant who sells them for a total of £ 50,000.
In the collection taken from Mr. Harrison's person, there is a water-stained official White Star Line sailing book for the Titanic. The book was changed on April 6, 1912, just four days before the liner left Southampton. It is expected to be sold for up to £ 18,000.
The collection of documents containing two other items found upon Mr. Harrison's death will be on sale on October 19.