With due respect: Later Christians invented a divine Jesus!

One of the common accusations is that Jesus was just a person who became a legend and eventually God. In other words, Jesus was retconned as God by later Christians.

1 Corinthians 15

However, a reading of Paul's writings will disprove that notion. In the first letter to the Corinthians, Paul recites the earliest Christian creed (1 Cor 5: 3–8). 

For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that he was buried, that he was raised on the third day according to the Scriptures, and that he appeared to Cephas, and then to the Twelve. 6 After that, he appeared to more than five hundred of the brothers and sisters at the same time, most of whom are still living, though some have fallen asleep. Then he appeared to James, then to all the apostles, 8 and last of all he appeared to me also, as to one abnormally born. -- 1 Corinthians 5: 3–8

Paul states that more than 500 hundred people saw Jesus die and came back to life (in fulfillment of the Scriptures; which showed that Jesus was who he claimed to be, i.e. God.).

Note that 1 Corinthians is estimated to be written around 54 AD, about 20 years after Jesus’s execution. Thus Paul’s claim could have been easily challenged by other Christians. As his record of events is backed by eyewitnesses and other apostles, it showed that Christians had regarded Jesus as God from the start.

Pliny the Younger
In 112 AD, Pliny the Younger (a Roman governer) wrote a letter to the Roman Emperor on the policy towards Christians (i.e. how to persecute Christians). In it, he described the religious practices of the Christians. He mentioned that Christians worshiped Jesus and even practised the a ritual of communal eating (i.e. the Holy Communion).

Other sources of early Christian worship are recorded by historians Josephus, Tacitus and Suetonius.

Conclusion

Early Christians did worship Jesus as God.