There is a database available here:
https://www.slavevoyages.org/voyage/database
In theory, you can download the data as a CSV, though it seems rather slow. Once you download as CSV, you can should be able to Import into Wolfram Language as a Dataset.
slaveDB=Import[myfile,"Dataset",HeaderLines->1]
From there, you have huge amounts of functionality available, particularly if you can integrate it with geographic information.
