Question

[Egeria]

The Cistercians are a reform of the Benedictines, so they are medieval and far from first. The rule of Caesarius of Arles predates Benedict's, I believe, but not that of Basil. 

​Nunsuch, the question was about the first Order, which, to the best of my knowledge, was the Cistercians. They were founded at the beginning of the period when Orders emerged, although my memory is hazy on the details of that. Rules are another matter entirely and given that Cistercians follow the Rule of St Benedict, they could hardly be the first. 

[Egeria]

On the subject of Rules, there is also the Rule of the Master, which was written before that of St Benedict and which influenced him although he also modified it.

Another crucial influence, together with St Basil, was St John Cassian (and St Benedict directs his disciples to both of these at the end of his Rule). Although his Institutes are not normally spoken of as a "Rule," the way a monastic rule came to be understood in the West has also developed and is seen in more formal terms to how it is seen in the East. 

[John Paul]

I read the Rule of the Master at New Melleray Abbey!

Almost the same chapter names!

[NadaTeTurbe]

Egeria, I think I do not understand, what is an order ? Why are cistercian an order and benedictine not ? 

 

[Egeria]

Nada, I don't remember all the historical details, and I never was much good at the canonical aspects, but to put it simply (and this is probably an over-simplification as I vaguely remember some exceptions to the rule), until then one simply had autonomous monasteries that followed the Rule of St Benedict but were not joined in any Order. When the Cistercians were founded, they also did not set out to found a new order, but simply a monastery - at Citeaux - in which they could live the Rule more authentically. But because of their rapid growth that led to new foundations, they sought a way of uniting the different houses in order to maintain their fervour and assist one another. This resulted in the Charter of Charity and a General Chapter of Abbots and led to the development of what became a religious order. There is a bit more on this history here that notes that "the Fourth Lateran Council (1215), pointing to the Cistercians as a model, enjoined governance by general chapter upon all religious institutions of the age that had not already adopted it." 

As for the Benedictines, I'm no expert here, but although they are called an Order, they are not really an Order in the same sense, but are rather a confederation of different monastic Congregations. (And although many Benedictines put OSB - signifying membership of an Order - after their name, I am told that this is a rather recent development).

[marigold]

Yes, this ^^^^^^^^