The first house suggests everything about you: your personality, your appearance, and all that is dearly important to you. Your desires that are covered by the first house are so personal to you that no one, not even your astrologer, would be able to guess what they might be. It covers your ego and natural tendencies as well as your determination and your will. The first house describes the face you show to the world.
With regard to health, the first house rules your vitality and energy. The first house works with the sixth house, which rules preventative measures you take to stay strong and healthy, and with the eighth house, which rules surgery, should it be needed. The twelfth house rules the subconscious and psychological matters.
When I speak of surgery or psychological matters, none may be indicated, but if a questions should come up, those are the houses that an astrologer would look to for clues to create an informed answer.
Special note: The “ascendant” is the sign found on the cusp of the first house and comprises this house. Another word for ascendant is the “rising sign,” which means the same thing. The ascendant, or rising sign, is the sign found on the eastern horizon at the moment you were born. It can only be ascertained by an astrologer casting a custom chart for you using your exact time and location of birth. All charts in the world are first converted to Greenwich Mean Time, England, as the common denominator.
If you have had your chart done and know your ascendant, you should read both for your Sun sign and your ascendant sign in all forecasts and personality reviews. They are equal in importance. The ascendant is the sign whose characteristics you adopt at birth and express naturally. (This explains why all Aries are not alike and so forth—most people are a combination of two signs—their Sun and rising signs.) People who were born at dawn have the same rising sign as their Sun sign. The time the Sun comes up at dawn changes with the season, as daybreak happens earlier in the summer than it does in the winter.
Each sign of the zodiac is ruled by a planet, so once you know your rising sign, note where and in what sign that planet is placed—it is one of the key engines that run your chart. Look, too, to the ruling planet of your Sun sign. This is why cusp babies need to know their precise time of birth—to know their accurate chart in order to forecast important events.
The first house is naturally ruled by feisty, individualistic, entrepreneurial, energetic, and action-oriented Mars and the first sign of the zodiac, Aries. Your own rising sign would dominate this house, but underneath your rising sign, the first house still echoes the classic high energy of Mars and Aries as the sign most closely associated with all things new and the renewal of life.