Traditionally described as the lesser malefic (Saturn being the greater malefic), Mars rules Aries, cardinal fire, and Scorpio, fixed water, and it is exalted in Capricorn.

Mars in by nature fiery and in many respects resembles the Sun. its action, however, is more energising and less stable; it gives physical activity, enterprise, courage and endurance, showing the more positive side through Aries and the more negative side through Scorpio. It bestows nerve, muscular power, and the ability to “rough it”.

It is quick, decisive, restless, apt to do things single-handed, and “run the show”, believing that no one else can do as well. If prominent there is seldom great refinement, the tendency being to get on with things and not beat about the bush.
Mars energy is extremely individualistic, causing one to emphasise difference unlike Venus who emphasises similarities. Thus one persons Mars may be a threat to another’s. This is the source of conflict: the inability of two people’s Mars energies to operate in the same space.

Like the Sun, Mars energy enables us to get things done. But it is only effective when it works for an entity’s survival and self-expression. Mar’s energy is self-centred, not altruistic although it can appear selfless.

Domineering or bullying behaviour is not the style of a healthy Mars. Those who thrill to the glory of competition and enjoy testing their courage are really the ones in whom Mars is strong. The strongest Mars types have little desire to compare themselves to others. They prefer to improve on their own performance, constantly becoming better and stronger.

Thus the Mars type is an individualist. Mars people do not want to compromise their integrity by following a path set by another, so this type is often the first to go where none has gone before. The true Mars type wants neither to dominate nor be dominated, but wishes to be left alone, free to pursue whatever path is desired. For this reason the Mars type may have difficulty in relationships.
Women will often experience their own Mars energies through men. Hence Mars, like the Sun, is said to rule males. But anyone can experience Mars through other people who are associated with force, strength and vigour.

In a healthy body, Mars represents the vigour and vitality of movement, especially the muscles. But it can also manifest as irritations, inflammations, infections and fevers. Mars can be one of the principal significator of operations and accidents. These difficulties occur when the normal psychological channels for Mars expression become blocked.

Neither Venus nor Mars alone is the planet of sexuality. It is the combination of the two that rules sexual passion. The intensity of sexual passion is the result simultaneously of the expression of selfish energies (Mars) and an experience of merging (Venus). Keeping the balance between the two energies is one of the difficulties in sexual relationships.

One of the most peculiar attributes of Mars is its faculty of identification. In its crudest form Mars is concerned with biological survival, but Mars energy may become transferred to matters that have to do with survival on a psychological level. Mars energies may become identified with one’s possessions, social status, career, credibility, reputation etc.

Correct use of the Mars principle can make for courage and endurance. Courage does not necessarily mean aggression or fighting. Courage means fighting those things we are frightened of. Aspects to our Mars, along with the sign and house placement, will suggest what tools we have to defend ourselves with and maintain our position in given situations.

Mars will also quicken the expression of whatever planet it touches in the birth chart. That planet will be speeded up and the individual will be impatient to express it, and in this area, if in no others, the person may come on strong.