The contingency spell description states:
Choose a spell of 5th level or lower that you can cast, that has a casting time of 1 action, and that can target you.
What intrigues me is
The contingent spell takes effect only on you, even if it can normally target others.
For instance, the crusader's mantle spell (PHB, p. 230) says:
Holy power radiates from you in an aura with a 30-foot radius, awakening boldness in friendly creatures. Until the spell ends, the aura moves with you, centered on you. While in the aura, each nonhostile creature in the aura (including you) deals an extra 1d4 radiant damage when it hits with a weapon attack.
Does this mean that if I cast Contingency with an area-of-effect/aura spell, it will only affect myself?