The Baritone was created in the 1940's and has the tuning D-G-B-E (from top string to bottom) which is the same as the first four strings of the guitar.
The Bass `Ukulele or, more correctly, the Contrabass `Ukulele has the same tuning as an upright bass. The first bass `ukulele became available on the market in 2009, with an octave higher tuning. The Contrabass `Ukulele, which is what we now normally refer to as the Bass `Ukulele, became available on the market in 2012. However, independent luthiers in Hawai`i have created a few before 2009.