The law was changed to allow girls to inherit the British throne on 28 October 2011. A summit was held in Perth, Australia, at which all the members of the Commonwealth (the group of 16 countries of which the UK monarch is the official head) voted. They agreed unanimously to change the line of succession. The effect of this is that potentially a daughter of the next in line to the throne, Prince William, could succeed to the throne over a younger brother. At the time the law was passed, it was of course quite likely that Prince William and Princess Catherine’s first child would be a girl, so it seemed important to get this sorted out. In fact, in 2013 their first child was born and it was a boy (George) so in fact the question may not arise for some time. But it was also thought important to send out a message that the monarchy is in touch with modern attitudes and doesn’t discriminate against women. At the same time, a ban on Roman Catholics inheriting the throne was also lifted – the ban goes back hundreds of years. The changes in the law are quite complex and a number of old pieces of legislation will have to be amended to bring them into line with it.
It may seem surprising that, almost 40 years after women were given official equality with men in the UK, the succession remained only male until this law was passed. But in the first place, the royal family as an institution obviously isn’t really about equality – you have to be descended from the Hanoverian family that founded the House of Windsor in the 18th century, in order to inherit – and in the second place, the question for many years didn’t seem very urgent. Back in the early 1980s when Prince Charles married his first wife, the late Lady Diana Spencer, the question was raised; but as they went on to have two sons it was clear that for a long time to come, changing the law wouldn’t make any difference.
The previous laws of succession were over 300 years old. Under this law the monarch’s oldest son would always inherit, with a daughter only succeeding to the throne if she had no brothers. However, in the case of the landed aristocracy the situation often was, and is, even more discriminatory. While laws do vary, the typical situation is that daughters of noble families can’t inherit the estate or the title at all – so even if a daughter is the only child of, say, an Earl, she can’t be left the property when he dies. It will pass to the nearest male relative, who in some cases may be quite a distant one. In a recent case, a woman who had lived and worked on her father’s estate all her life was passed over in favour of a cousin who, until that time, had not even known that he was in line to inherit the estate and didn’t even want it.
The change in the law of succession has prompted many aristocratic families – especially, as you many not be surprised to hear, the daughters – to demand a change in the law for them too. Some people argue that since the whole system of peerage is founded on inequality anyway, there is no reason why that shouldn’t include gender inequality too, but others feel that it should be possible for the children of a landowner, who will have grown up on the property and are likely to know how to look after it, to inherit it.
You can find an overview of the situation here.