Vitalik Buterin proposed the ethereum protocol in his 2013 whitepaper with the goal of creating a general purpose blockchain platform to support decentralized applications and smart contracts. Buterin had previously contributed within the Bitcoin developer community and found limitations to the Bitcoin scripting language including lack of Turing-completeness, value-blindness, lack of state, and blockchain-blindness. Ethereum was formally announced at the North American Bitcoin Conference in Miami, Florida (2014).
In early 2014 additional developers joined Buterin, including Gavin Wood and Jeffrey Wilcke listed as Lead C++ Developer and Lead Go Developer respectively as well as Anthony Di Iorio, Mihai Alisie, Joseph Lubin, and Stephen Tual in primarily non-development roles. The Ethereum Foundation (Stiftung Ethereum) was founded in July 2014 in Switzerland.
By April 2014, Gavin Wood published the Ethereum Yellow Paper describing the formal definition and technical specifications of the Ethereum Virtual Machine (EVM).
Ethereum was funded by an initial coin offering (ICO) launched in July 2014. According to the Ethereum foundation, within the first two weeks more than 50 million ETH were sold. In total, the 42-day public ether pre-sale raised 31,591 bitcoins worth approximately $18 million dollars at the time.
Prior to the official launch of Ethereum, a series of proof of concept versions of were released culminating in the beta release named Olympic on May 9th, 2015. The purpose of Olympic was to engage the community to stress test the network, build decentralized applications, and start running nodes. Total rewards of 25,000 ethers were distributed to community members for contributions in the four categories of transaction activity, virtual machine usage, mining prowess, and general punishment.
The initial public launch named Frontier was released on July 30, 2015. This release provided instructions for generating the first block in the ethereum blockchain known as the genesis block, which was created with a unique parameter from the hash of the ethereum testnet block #1028201 and contained all transactions from the ethereum crowdsale.
The second major release of ethereum named Homestead went live on March 14th, 2016 on block 1,150,000. Homestead included protocol changes providing changes to the network giving increased ability for further upgrades, improved transaction speed, and improved security.
The Metropolis release will be split into two parts – the first of which called Byzantium was released on block 4,370,000 on October 16, 2017. The Byzantium release introduced privacy features zk-snarks and zero-knowledge proofs to the ethereum blockchain, a feature added due to collaboration with the developers of Zcash including Zooko Wilcox. Additionally, the Metropolis release will include account abstraction, return data, and revert capabilities. The release date for second part of metropolis named Constantinople has not yet been determined.
The last planned release of ethereum named Serenity plans to include features to transition ethereum from a proof-of-work consensus protocol to a proof-of-stake based on the Casper protocol being developed by Vitalik Buterin, Vlad Zamfir, and others. Serenity is also scheduled to implement sharding.