This document summarizes research on the energy level structure and transition probabilities in the spectra of trivalent lanthanides doped in LaF3 crystals. It presents experimental data on the absorption spectra of lanthanide-doped LaF3 from 4000-50000 cm-1. It also describes theoretical models used to interpret the spectra and calculate atomic and crystal field parameters. The models were optimized to fit the experimental data and identify trends in the parameters across the lanthanide series. Lifetimes of excited states were also calculated and compared to experimental measurements.