Your male cat suddenly starts jumping on other household cats, biting and swatting them. He has even bitten you once or twice. Although he didn't draw blood, you're worried that he might get mean. Why is he doing that? The random, unpredictable attacks, which are undertaken without inflicting any damage, sound very much like mating behavior. Sexually intact males are ready to start breeding from about 5 months of age. This age varies widely among breeds, but a good rule of thumb is that the long, slender cats, Siamese, Oriental shorthair, and Abyssinian types, have been known to exhibit breeding behavior as early as 4 months, with 5 months being a fairly common age for entering puberty. Medium-bodied cats, such as Maine Coons, Ragdolls, and Norwegian Forest Cats generally become sexually mature at 7 or 8 months, and stocky and cobby cats, such as Persians and Exotic Shorthairs, may not show any interest in breeding until they are as old as 2 years.
The aggression shown in breeding does not have any anger behind it, which is why your other cats will not stay mad at your aggressive male cat for attempting to breed them. Usually sexually excited male can simply wait for an opportunity, such as when the female has her back to him, before attempting to breed. The bites are not painful and do not do any damage. Occasionally a very reluctant female may escape from a very determined male and lose a chunk of hair in the process.
The way to make your aggressive male cat stop attacking you and other cats in the household, and consequently turn him into a calmer, more loving pet, is to have him neutered. Your veterinarian can give you a long list of the benefits you male cat will receive from being neutered. Neutered males make better pets. If they are neutered before they start spraying, they do not spray urine on furniture and walls in an effort to announce their sexial availability to females. They do not beat down the doors or claw or bash their way through the window or door screens in an effort to meet with neighborhood females who are in heat, and they do not get into fights with other toms over females. Even if you allow you male cat to go outdoors, he will stick closer to home and be less likely to get into territorial fights with other cats.