I think it was with the seq2seq paper of Sutskever, Vinyals and Le in 2014: https://arxiv.org/abs/1409.3215 https://arxiv.org/abs/1409.3215 People were doing a

I think it was with the seq2seq paper of Sutskever, Vinyals and Le in 2014: https://arxiv.org/abs/1409.3215 https://arxiv.org/abs/1409.3215 People were doing a mix of learning from data and hand engineered solutions before this, but this was the first system learned end-to-end, afaik.