The oldest surviving deck we have is the Visconti-Sforza, made in 15th-century Italy. Most historians place tarot’s origins around then, but it started out as a set of playing cards - the divinatory use came later.
With Rider-Waite, the Major Arcana borrows from earlier decks but introduced lots of new symbolism and reworked several images. The Lovers is a good example: compare the Marseilles version to Rider-Waite and you’ll see they’re portrayed and read very differently.
The Minor Arcana in Rider-Waite are largely original to that deck. Arthur Waite guided the project and worked closely with Pamela Colman-Smith, who illustrated it. He gave the brief, but recent research argues Colman-Smith - who was involved with the Order of the Golden Dawn - probably contributed more of her own ideas than was originally credited.