Tales of rags and riches revealed as wills of the famous go online

Official summaries of more than six million wills dating from between 1861 and 1941 were scanned and uploaded by family history website Ancestry.co.uk.

The "probate calendar books" for England and Wales are an index giving details of how much the estates were worth, and in some cases who inherited them.

As well as helping people researching their own family trees, the records give a fascinating insight into the financial affairs of famous politicians and writers.

They show that Marx, the German communist philosopher who died in north London in 1883, left just 250 (worth 23,000 today) to his youngest daughter Eleanor.

By contrast Charles Darwin, the naturalist who set out the groundbreaking theory of evolution in The Origin Of Species, left a personal estate worth 146,911 (around 13m today) at his death in 1882.

He was nearly twice as wealthy as the novelist Charles Dickens, who left "effects under 80,000" (about 7.1m today) when he died in 1870.

The probate calendar books show that Sir Ernest Shackleton, the Anglo-Irish polar explorer who lost his fortune in failed money-making schemes, left an estate of just 556 (20,000 today) at his death in 1922.

Also included in the records are former prime minister Neville Chamberlain (who left 84,013 in 1940, worth just over 4m today) and authors Arthur Conan Doyle (63,491 in 1931, worth 3m today) and Lewis Carroll (4,145 in 1898, worth 450,000 today).

The international content director of Ancestry.co.uk, Dan Jones, said: "The probate calendar books provide countless new leads for family historians to explore as they move beyond being about family members to long-gone fortunes, mysterious beneficiaries and valuable objects – all with connections back to our ancestors just waiting to be explored.

"Anyone able to find an ancestor in the probate calendar books will be able to find out a great deal about how their ancestor lived, what they bequeathed and to whom – meaning we will be able to find out so much more about what their lives would have been like."