He was the son of Jergon Abelseth and Anna Hatlevik, living at a farm in Ørskog - east of Ålesund a small fishing village in Norway.
Olaus had worked as a sailor and casual labourer. He went to America with his brother Hans in 1902 or 1903 and lived in Hatton, North Dakota where he worked on different farms in the Red River Valley.
In 1908 he established a livestock farm in Perkins County, South Dakota. After a difficult period at his farm Olaus decided to visit his relatives in Norway and he departed for Glasgow by steamship from New York in the late Autumn of 1911. From Glasgow he continued his journey to Scandinavia.
In April 1912 Olaus began the return journey, his stated destination was Johan B. Abelseth 1112 Lincoln St. Minneapolis. Travelling with him were five other Norwegians: Adolf Humblen, Anna Salkjelsvik, Peter Søholt (a cousin), Sigurd Hansen Moen (married to Olaus' sister Inge) and Karen Marie Abelseth. Karen Abelseth was not a relative (? a cousin) but was the daughter of one of Olaus' neighbours when he lived in Norway. They new each other well, so, since Karen was only 16, her father asked Olaus if he could look after her on the trip to America.
The party set sail from Ålesund to Newcastle via Bergen and boarded the Titanic at Southampton. Olaus and Humblen shared a cabin toward the bow on F Deck (G-63) from where, on the night of the disaster, he made his way aft along the working alleyway Scotland Road on E Deck to meet Karen. He finally found her near the main third class staircase towards the stern and then she, Olaus and the rest of their group made their way to the aft well deck.
They waited on the poop deck for instructions. At about 1:30 third class women were finally allowed onto the Boat Deck, followed by the men at 2:00. While many decided to remain on the poop Olaus and his relatives made for the Boat Deck. Olous together with Moen and Søholt placed Karen Abelseth into a boat.
With the last boat pulling away they heard a call for sailors, some of the crew were trying to free a collapsible and Olaus who had six years of sailing experience as a fisherman was tempted to assist but his cousin and brother in law urged him to stay with them.
When all the boats had gone Olaus and his relatives found themselves near the fourth funnel, as the Titanic sank deeper they clung to the falls of a lifeboat davit. His brother in law urged him to jump for it but Olaus waited. When the water was only five feet away they plunged in. As he surfaced Olaus became entangled in a line but somehow managed to break free, when he looked around him his brother in law and cousin were nowhere to be seen, they had been washed away.
Olaus swam for twenty minutes in the icy water before finally reaching Collapsible A. Surrounded by dead and dying he tried to pull himself into the waterlogged boat but someone inside shouted 'don't capsize the boat', so Olaus clung to the side for a while before eventually dragging himself aboard.
As they rowed through the night the survivors in Collapsible A prayed, and, although nearly waist deep in water Olaus tried to revive a fellow passenger who lay freezing in the bottom of the boat, he lifted him up and discovered that it was a man from New Jersey with whom Olaus had shared a carriage on the boat train to Southampton. When the Carpathia was sighted he urged the man to look up, but as dawn broke the man slipped away. Another man put his arms around Abelseth to relieve cramps caused by the cold but eventually he too died, and Olaus had to pry the man's arm off him.
When he finally reached the deck of the Carpathia at 7:00 am he was given a warm blanket he then headed for the dining room for some brandy and a hot coffee. With cabin space at a premium Olaus found he had to sleep on deck and lay down to sleep in the same clothes that he had worn all night in the flooded boat.
In New York he stayed a few days at St. Vincent Hospital. He also testified before the US senate Inquiry before moving on to Minneapolis. During 1912 and 1913 he travelled in Canada, Indianapolis and Montana before returning to his farm in South Dakota.
In July 1915 he married Anna Grinde in South Dakota. Anna was Ole's first wife, he her second husband. Anna had been born in Grinde Norway October 6th, 1877. Her father had died at sea in Norwegian waters near Sognefjorden on 19 June 1886. The death occurred only nine day after Olaus was born, Anna was eight.
Olaus worked his farm for a further 30 years and he and Anna had four children; their second son died at the age of 3½, the other children were: George, Helen and Mae.
He retired in 1946 to Reeder, North Dakota. In 1948 they moved to Tacoma Washington and in 1960 to Whetting, North Dakota before settling in Hettinger, Adams Co., North Dakota.
Anna celebrated her 100th birthday in 1977; she died in August 1978. Olaus died on December 4th, 1980; he was the last survivor from Collapsible A and the last survivor to testify at the US Inquiry. His daughter Mae (Mrs Jim Omodt) lived in Sandpoint, Idaho2 and his son George in Prairie City, South Dakota.