Fritz Althaus was born in Lewisham, Kent, and first learned to draw with the help of his mother who was talented amateur portrait-painter. His father, born in Germany, was a Professor of Music.  He studied under the artist Axel H Haig, an artist who boarded with his family, followed by tutelage at St Martin's School of Art, the Westminster School of Art and the Royal Institution. Until 1893 he made his home in Maida Vale, London, while also travelling in the West Country, before deciding to move to Exeter. There he could paint along the coasts as far as Cornwall, including the Channel Islands. Oxford and Cambridge.

The artist is purported to have been a prolific marine painter up to 1900 (Brook-Hart), with over 50 oils and watercolours to his name. Almost all of his 18 RA exhibits were sea pieces off the Cornish and Devon coasts, one example being Cornish Luggers running for Shelter (1888). An 1893 painting, Trading vessels at their anchorage (w/c), is representative of his style.

Flanagan (2010) has also identified Althaus as painting in that other St Ives in Huntingdonshire in the 1880s and 90s, and reprints in colour Bridge Street, St Ives, 1902 which attests to his returning there to paint along the Ouse over at least three decades.

He exhibited and sold Sunset at NAG in October 1905, and Sullen Pool (Jan 1906). His NAG sales records extend his artistic activity by at least 6 years. By 1908 he was living in Headingley, Leeds and in 1909 he and his wife, Margaret Richardson Althaus (nee Henderson) had a son, Gerald Malcolm Theodore. In 1911 another son, Frederick John Basil, was born.

Because of the Great War, Althaus changed his name to Frederick B KERR (c1915).  In the name of Fred KERR he was made Professor of Art at Leeds University (Mallalieu). However, this is as yet unconfirmed information of his occupation, as on his death certificate he is identified as 'a schoolmaster retired', living at Valroy (81 or 87 unclear), London Road, Camberley.

He died in 1962, in Frimley, Surrey (the Frimley and Camberley District Hospital, now the Frimley Children's Centre, Church Road, Frimley) at the advanced age of 99 years and 8 months (Bednar research, GRO death certificate on file) from a late case of pneumonia and congestive cardiac failure. The name on his death certificate is Frederick Bernard Kerr, and was attested to by his son, the informant Lt Col F J B Kerr, also of Camberley.