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Insulator-to-metal transitions (IMT) are a hallmark of many families of quantum materials. Impulsively induced electronic phases are typically short-lived, with lifetimes on the order of the electromagnetic pulse width or the energy relaxation time of the material. Yet, in quantum materials with wrinkled free-energy landscapes, impulsive stimulation can trap the system in new metastable states and 'hidden' phases not apparent in common phase diagrams of quantum materials. Lanthanide sesquisulfides (Ln₂S₃) manifest unusual magnetic and electronic behavior. However, very few studies on Lanthanide sesquisulfides have been reported under pressure. In an effort to expand the understanding of La₂S₃, we performed Raman and resistance measurements up to 20 GPa. At low pressures between 16-18 GPa an interesting softening of the low frequency modes in the Raman was accompanied with laser driven resistance change, which provide an exciting opportunity to tune their exotic properties by impulsive stimulation harvesting metastable hidden phases of these materials.