There have been few papal statements on the issue of evolution. In general, the Church has declared that this subject is outside of its purview. Many overstate the assertions made by Pius XII in 1950, found in Humani Generis, sections 36 and 37.

(36) For these reasons the Teaching Authority of the Church does not forbid that, in conformity with the present state of human sciences and sacred theology, research and discussions, on the part of men experienced in both fields, take place with regard to the doctrine of evolution, in as far as it inquires into the origin of the human body as coming from pre-existent and living matter - for the Catholic faith obliges us to hold that souls are immediately created by God. However, this must be done in such a way that the reasons for both opinions, that is, those favorable and those unfavorable to evolution, be weighed and judged with the necessary seriousness, moderation and measure, and provided that all are prepared to submit to the judgment of the Church, to whom Christ has given the mission of interpreting authentically the Sacred Scriptures and of defending the dogmas of faith.[11] Some however, rashly transgress this liberty of discussion, when they act as if the origin of the human body from pre-existing and living matter were already completely certain and proved by the facts which have been discovered up to now and by reasoning on those facts, and as if there were nothing in the sources of divine revelation which demands the greatest moderation and caution in this question.

(37)When, however, there is question of another conjectural opinion, namely polygenism, the children of the Church by no means enjoy such liberty. For the faithful cannot embrace that opinion which maintains that either after Adam there existed on this earth true men who did not take their origin through natural generation from him as from the first parent of all, or that Adam represents a certain number of first parents. Now it is in no way apparent how such an opinion can be reconciled with that which the sources of revealed truth and the documents of the Teaching Authority of the Church propose with regard to original sin, which proceeds from a sin actually committed by an individual Adam and which, through generation, is passed on to all and is in everyone as his own.

A number of things should be pointed out about this statement. First, it is not an infallible statement (especially given that there have been so few of these statements made by pontiffs). It doesn't rise to the criteria necessary for that kind of proclamation. The statement also comes from a theological and philosophical document--not a scientific treatise. It also was written in 1950 and was compiled with the knowledge that the writer(s) had at that time. Further, section 36 has been emphasized by subsequent pontiffs but section 37 has not been as predominant (reference the below statements as well as other more recent statements than the rules of this subreddit would allow).

Speaking of other statements from pontiffs, we have this from John Paul II:

we have this from John Paul II in 1996:

Taking into account the state of scientific research at the time as well as of the requirements of theology, the encyclical Humani Generis considered the doctrine of "evolutionism" a serious hypothesis, worthy of investigation and in-depth study equal to that of the opposing hypothesis. Pius XII added two methodological conditions: that this opinion should not be adopted as though it were a certain, proven doctrine and as though one could totally prescind from revelation with regard to the questions it raises. He also spelled out the condition on which this opinion would be compatible with the Christian faith, a point to which I will return. Today, almost half a century after the publication of the encyclical, new knowledge has led to the recognition of the theory of evolution as more than a hypothesis. [Aujourdhui, près dun demi-siècle après la parution de l'encyclique, de nouvelles connaissances conduisent à reconnaitre dans la théorie de l'évolution plus qu'une hypothèse.] It is indeed remarkable that this theory has been progressively accepted by researchers, following a series of discoveries in various fields of knowledge. The convergence, neither sought nor fabricated, of the results of work that was conducted independently is in itself a significant argument in favor of this theory.

There is also this statement from Cardinal Ratzinger in 1995:

We cannot say: creation or evolution, inasmuch as these two things respond to two different realities. The story of the dust of the earth and the breath of God, which we just heard, does not in fact explain how human persons come to be but rather what they are. It explains their inmost origin and casts light on the project that they are. And, vice versa, the theory of evolution seeks to understand and describe biological developments. But in so doing it cannot explain where the 'project' of human persons comes from, nor their inner origin, nor their particular nature. To that extent we are faced here with two complementary—rather than mutually exclusive—realities

In summary, I would assert that the Catholic Church has made no definitive statement on the subject, preferring to stick to the theological implications rather than the scientific concerns.

I hope that answers your question. Followup questions are always encouraged (though I must admit that this is slightly outside my expertise, and my comments should be read more as how the papacy has responded to evolution rather than the Catholic Church as a whole or individuals within it).

Are you looking for an official response by the Catholic Church to Darwin's work or a history of the CC's handling of the theory of evolution?

With silence.

The period after the publication of Origin of Species saw a reactionary movement in Catholic doctrine. The "Syllabus of Errors" by Pius IX reinforced some of the most conservative parts of Catholic thought. The First Vatican Vouncil defined the doctrine of Papal Infallibility shortly after.

Despite this, Darwinian evolution was never attacked in the way Republicanism, Athiesm, etc were.

Here is a copy of the Syllabus of Errors. Notice

The decrees of the Apostolic See and of the Roman congregations impede the true progress of science.

is on the list of errors. Evolution isn't.

Unlike in Protestant fundamentalism, evolution never became an important topic for traditionalist Catholics.

These are all good answers, thanks.