The Emperor Card in Tarot is commonly aligned with the astrological sign Aries. In Tropical astrology (the astrological method most popular here in the West), Aries season starts on Spring Equinox. Therefore, the Emperor card can give great insight into the nature of the energy at the start of Spring. Even if you don’t subscribe to this (and lots of astrologers don’t) Aries is still thought of as the “first” sign, and so, it rules the first house of the chart. For many religious and cultural groups, Spring is the “start” of the year, energetically and calendar-wise as well.