In history, dual wielding is a bit of a rarity, Miyamoto Musashi taught a school of it, and the Florentine style of fencing was also a dual wielding technique that gained some prominence for a limited period of time, before falling out of fashion when firearms got a lot more reliable, easy to use, and became affordable and so more common still. Native Americans supposedly used Tomahawks and knives simultaneously. I am probably either forgetting some or unaware of others, so feel free to point me in the direction of other interesting examples.
Some Escrima techniques are also a dual wield.
Otherwise a shield was far more common (before firearms) and probably a better choice.
In fantasy there is a ton of dual wielding just pick your genre.
I could really care less if it is included my rogue prefers a bow and my fighter likes a Zweihander, so I doubt I will be making use of it even if it is included.
Still- always nice to have options, and in Baldurs Gate 2 and Icewind Dale's I occasionally had a character that dual wielded, a fighter/thief using a Scimatar and a shortsword, which for hi dexterity decent strength and no shield ability was OK.