In subsequent years (1983–1996) he published a large amount of the remaining unpublished materials, together with notes and extensive commentary, in a series of twelve volumes called The History of Middle-earth.
Nos seguintes anos (de 1983 a 1996) publicou unha gran cantidade de material adicional sen publicar ata o momento, xunto con anotacións e comentarios extensos, nunha serie de doce volumes titulada The History of Middle-earth.