do you believe the christianity gnosticism was the first christian church?

before the official catholic church, eastern orthodox and the today protestant sects?
the gnostic Christians are now disappeared? no

No.

Take the words 'Christianity' and 'christian' out of your question and you'll have the answer.

Gnosticism was one of the outliers -- outside the beliefs of the Christian Church, and thus not part of the early catholic church.

Gnosticism is alive and well, but it is not Christian. There are no secret bits of knowledge in Christianity.

Blessings.
/Orthodox

No, Gnosticism is far wider than Christo-Gnostic groups who were very diverse doctrinally from each other

The One Holy Catholic Apostolic Orthodox Christian Church blossomed as the Nicene Trinitarian Incarnation-believing Church not as a gnostic one or umbrella group and all its institutions, dogmas, sacraments, etc were there in seed from the beginning of Christianity

The R Catholic and E Orthodox split around 1054Ad and the Oriental "Monophysite"Orthodox around 451AD and the Assyrian/ Persian/Far eastern 'Nestorian"around 431AD or later

Christo-Gnosticism has had revivals ( as with the Cathars) and grew in the late 19Th a ND early 20 Th cent (with Theosophy, Christian Science, etc)

Gnosticism came during the period of the first council of Nicea. Basically all the different sects came together to debate which is the correct form of Christianity. Gnosticism(not one united idea but numerous groups were Gnostic's) was viewed as unrelated to Christ so it was largely abandoned by its followers when the debates were completed and joined the Catholic fold.

At different periods some people got interested in Gnosticism but never in large numbers. Usually just individuals reading the old gnostic writings.

You may want to read the book 'Piso Christ'.

The author Roman Piso has said that the so-called Gnostic texts were written by the same family that wrote the other Christian texts.

In the first century of the common era, the psychopath Arrius Calpurnius Piso instigated a war with the Jews and went to work creating Christianity as a means to recreate the world into a place that would be as a paradise to psychopaths such as himself.

One of the main things which has prevented other scholars from discovering this is the fact that they were looking at and studying the ancient Christians texts and related material as if they were written by non-psychopaths. The key to understanding and thus, proving the psychopathic link between Arrius Piso (aka Flavius Josephus) and the New Testament texts (and Christianity) is something called 'psychopath speak'. That is a type of 'speak' or way of saying or stating things which is used exclusively by psychopaths.