Just over half of these (51%) had no academic qualifications.
Overall, Scotland's historic image as an industrial nation took a further blow as the figures revealed half of those of working age had clerical, professional or administrative jobs.
Skilled manual workers represented just 24% of the population aged 16-64.
Small employers and the self-employed accounted for 295,000 people - 7% of the population aged between 16 and 74.
Men were most likely to be self-employed (11%), compared to 4% for women.
In 2011, over one quarter (27%) of the 4m people aged 16 to 74 in Scotland held a degree, compared to the 23% with no qualifications.
Among the other findings are that among the Asian population 21% worked in retail activities with a further 20% in food services.
White people were more likely (16%) to work in manufacturing and construction than those from minority ethnic groups (6%).
The census was taken in the depth of the credit crunch, and it revealed almost one third (32%) of full-time students had jobs, while 59% were economically inactive.
Almost 200,000 Scots aged 16-74 had never worked or were long-term unemployed, figures gathered in the 2011 census have revealed.