The first house determines a lot about what makes you unique — what you look like, your personality, your drive, your goals, and your priorities. It covers your ego, natural tendencies, the way you present yourself to the world, your energy, vitality and your deepest desires.
The first house, when viewed along with conditions in the sixth house (more on that one later) also reflects the state of your health and your vitality.
We look to the first house for any new, important trends and cycles. The first house is the hardest house for an astrologer to read, because your desires are so personal! It also rules your strength of will, your individuality and determination.
The first house reveals the sign rising on the horizon at your birth, also called the ascendant sign. The only way you can find out your rising sign is if you cast a natal horoscope chart for the exact date, time and place of your birth. (All charts are converted to Greenwich Mean Time. Astrology is very concerned with mathematical measurements; we convert everyone to the same birth city to create a common denominator.)
The sign on your ascendant is the sign whose characteristics you express naturally. This explains why all those born under the same sun sign are not alike; most of us are actually a combination of the sun sign and the ascendant.
Once you know your ascendant, you should read both your Sun sign and your ascendant sign, whether in forecasts or personality outlines; reading both will give you a more accurate picture.
The first house is ruled by feisty, entrepreneurial, energetic Mars and by the first sign of the zodiac, individualistic Aries.