During the War of the League of Cambrai, the French army invaded the city of Breschia in the Lombardy area of Italy. The city defended itself for seven days, but when the French broke through they went on a rampage of revenge and slaughter that killed off over forty-five thousand of the cities residents.
It was on this day (Feb 19) in 1512 that one of those French Soldiers slashed a twelve year old boy across the face with a sabre disfiguring the childs palete to the point that he acquired the nickname "Tartaglia", the stutterer, because of his difficulty speaking. Tartaglia went on to be a very good mathematician and is remembered mostly today for his conflict with the great Cardano, but when his birth name is given at all, it seems it may be mostly given wrong.
Tartaglia's father died when he was only six years old, and it seems that the only recorded name for him was Michiel di Bressa, refering to his being from bressia (today Brescia). In this period in Italian History it was not unusual for people not to have a "family" name but to use such a topological reference; think of Leonardo da Vinci, for example. If you search Tartaglia on the internet you will find his name given, most often, as Niccolo (sometimes Niccoli) Fontana. That's what it says on Wikipedia, and even at the usually very reliable St Andrews Math History web page. That's what I thought was true for most of the years I taught, and so some of my student's (the ones who actually listended to my little history asides in math class) may have thought so too.
A while back I came across a nice article by Friedrich Katscher at the MAA’s Convergence web site that explained part of the confusion, but not all. Professor Katscher even offers to pay big money ($1000 US) to anyone who can find any document where Tartaglia called himself Fontana, base on some pretty extensive research at Austrian an Italian reference libraries. The story of how that mistake might have been made is pretty credible to me. Three days before his death on December 13, 1557, Tartaglia appointed his brother as his legal heir. His brother went by the name of John Peter (Zuampiero) Fontana. No reason is given for the brother having adopted the name Fontana, but afterwards, historians assumed this was in fact the name of the long dead father, and Tartaglia as well.
The Professor stated that in all his Italian works, he only used, "Tartalea or Tartaglia", two variants of the nickname he acquired as a child. I would imagine if he assumed this as his personal name, he had grown past the severe speaking problem that earned him the nickname, but have no evidence of that. " I own facsimile editions of two of his works and even the original of his first book, La Nova Scientia, edition of 1550. Not only in all titles of his works you find the author Nicolo Tartaglia (before 1550 Tartalea) but he described also conversations he had, and published correspondences. In every talk, and in every correspondence he was always called Nicolo Tartalea or Tartaglia and he himself signed only Nicolo Tartalea or Tartaglia."
Additional compelling proof that Nicolo did not go by the name Fontana is given by the fact that, "The notary public Rocho de Benedetti had the duty to write the proper name of the decedent. But although he must have noticed that his brother had the family name Fontana he called the testator Nicolo Tartaia or Tartalea, and not Fontana. The notary also did not call his father Michele Fontana but in Italian Michiel di Bressa... "
As far as the use of Niccolo (Niccoli) as often used (Strangely the St Andrews site spells the name with one c in one place and two in another.) , the Professor merely proclaims "The spelling of his given name, Niccolò, found in many papers and books, even Italian ones, is wrong!"
The actual MAA posting is here.