Giovanni Battista Viotti (12 May 1755 – 3 March 1824) was an Italian violinist whose virtuosity was famed and whose work as a composer featured a prominent violin and an appealing lyrical tunefulness.

Viotti was born at Fontanetto Po in the Kingdom of Sardinia (today in the province of Vercelli, Piedmont, Italy).

He served at the Savoia court in Turin, 1773–80, then toured as a soloist, at first with Pugnani, before going to Paris alone, where he made his début at the Concert Spirituel, 17 March 1782.

When the French Revolution took a radical turn and, though his opera house was renamed the Théâtre Feydeau, former royal connections became a dangerous liability, he moved in 1792 to London, making his début at Johann Peter Salomon's Hanover Square Concert, 7 February 1793.

The Morning Post and Gazetteer in its issue of Friday, 9 March 1798, reported that "the Duke of L... and the Earl of C... have been particularly active in entreating his Majesty to order Viotti out of the kingdom".

In July 1811, he became a naturalised British citizen, after his friend, the Duke of Cambridge, a younger brother of the Prince of Wales, had interceded on his behalf.

The Viotti ex-Bruce, renamed in honour of its previous owner, was purchased by the Royal Academy of Music in September 2005.

The Viotti ex-Bruce is to be heard as well as seen: the instrument is to be played sparingly, under very controlled circumstances, at research events and occasional performances elsewhere.

Most likely they are the unpublished concertos mentioned by Viotti himself in his will left in favour of Mrs. Chinnery who cared for him in London, in the last years of his life.

In the meantime, in 2021, Guido Rimonda started the first publishing of Viotti's complete scores of violin concertos for Edizioni Curci Milan.

Most of his string quartets largely ignore the balanced texture pioneered by Haydn, giving a "solo" role to the first violin and as such may be considered Quatuors brillants.

The Italian violinist Guido Rimonda has pointed out in 2013[4] that the incipit of his "Tema e variazioni in Do maggiore" has a very strong resemblance to the French hymn La Marseillaise.