The following timeline documents the formative events that created and defined Ethereum Classic, and all major events to the present day.
For a more detailed investigation into the creation of ETC, please check out Genesis.
The network implements an ‘Ice Age’ at block 200,000 introducing the Difficulty Bomb, a mechanism designed to move the network's consensus mechanism away from Proof-of-Work to Proof-of-Stake.
With 12 hours notice, The Ethereum Foundation use a controversial third party 'coin vote' to determine that the Hard Fork should be turned on by default; consensus is declared, and an updated client is released.
A forked-chain is born! The Ethereum Foundation creates an altered version of Ethereum on July 20 2016 to reverse the DAO theft. As trademark rights holders, the Ethereum Foundation applies the Ethereum (ETH) brand to the new forked chain.
With predictions of the original non-forked chain to disappear within hours, many are surprised to find that miners continue to support the original chain. Bisq and OTC desks give these tokens a price discovery order book. The markets participants rebrand this non-forked chain Ethereum Classic (ETC).
The ETH community lets out a sigh of relief as the DAO fork code is successfully implemented with no obvious flaws; champagne corks are popped all over the globe. The birth of a new chain is a success!
Geth releases support for Ethereum Classic network. This node has all the DAO code removed from the client and requires no additional flags to use the Ethereum Classic network.
Parity signals long term support for Ethereum Classic with 1.2.3 release that addresses network stability issues for both Ethereum HF and Ethereum Classic chains and brings a few changes to the transaction tracing API.
After the ETC network grew to a point where they could no longer attack it, ETH miners publicly declare not to attack ETC. To prevent hurting innocent Ethereum Classic holders, ETHash miners commit resources to mining ETC.
After relentless attacks from the ETH side of the chain split, Ethereum Classic supporters stand firm and declare their independence from the new ETH chain.
Ethereum Classic proves its resilience to the markets as ETC emerges from the ETH attacks with a stabilizing price. The networks core principles are galvanized during the DAO Bailout. Supporters begin rebuilding from the ashes.
Both Ethereum networks are attacked due to vulnerabilities in the tech stack. ETC devs quickly ensure a smooth and non-contentious network upgrade to patch exploited vulnerabilities.
Ethereum Classic forms consensus around a 210.7M ETC fixed-cap monetary policy with a Bitcoin-inspired limited emission schedule called 5M20; 20% block reward reduction every 5M blocks.
Grayscale signals long-term support for Ethereum Classic protocol development by sponsoring the ETC Cooperative team with a portion of their ETCG management fees. Donations to the non-profit are tax-deductable.
The Multi-Geth client project launches. This is a go-ethereum client forked from Ethereum Foundation's version, aimed to follow closely for upstream changes, and support multiple Ethereum networks. We have just added alpha support for Ethereum Classic network.
ETC safely disables the difficulty bomb to switch the original Ethereum project to PoS. Ethereum Classic signals long-term commitment to Proof of Work as a network consensus mechanism.
ETC Cooperative funds the development of the Kotti testnet, a Proof-of-Authority testnet constructed to provide interoperability testing with sister-chain ETH's Görli Testnet. PoA becomes the preferred testnet environment for dapp development testing.
The 51% attacker appears to be a whitehat hacker and returns stolen funds to a compromised exchange. Centralized exchanges tighten 51% attack monitoring on Proof of Work coins across the board.
The ETC Core team forks away from the Multi-Geth client project. The project is named Core-Geth, an ethereum/go-ethereum downstream effort to make the Ethereum Protocol accessible and extensible for a diverse ecosystem.
During Aztlán testnet implementations, Ethereum Classic core developers discover complications with ECIP 1061 specs to add ETH's Istanbul network protocol upgrade. As intended, the ETC testnets catch the issues and core developers spec a patch for the issues.
ECIP 1050 Status Codes moves to Final status. This standard outlines a common set of Status Codes in the same vein as HTTP statuses. This provides a shared set of signals to allow smart contracts to react to situations autonomously, expose localized error messages to users, and so on.
During Aztlán testnet implementations, Ethereum Classic core developers discover complications with ECIP 1061 and 1078 specs to add ETH's Istanbul network protocol upgrade. Meowbits of ETC Core documents the findings. As intended, the ETC testnets catch the issues and core developers go back to the drawing board.
Based on the issues discovered during Aztlán testnet implementation, Phoenix Fix being found to not be a sufficient fix and both testnets breaking; the Core developers proposes to reject ecips-1061, 1078, 1086 due to security and stability concerns and to move on with writing a new proposal from scratch.
Ethereum Classic core developers reach rough consensus on ECIP-1088 in an effort to implement ETH's Istanbul network protocol upgrade. Testnet implementations revealed issues with prior attempts in specs ECIP-1061 and ECIP-1078.
Phoenix testing begins on the Mordor PoW testnet on block 999,983. Core development teams have signaled that this is a complex implementation. Testing may uncover issues that delay this network upgrade, but Ethereum Classic will never rush to upgrade the mainnet. Network security is priority over development speed and arbitrary timelines.
Phoenix testing begins on the Kotti PoA testnet on block 2,200,013. Core development teams have signaled that this is a complex implementation. Testing may uncover issues that delay this network upgrade, but Ethereum Classic will never rush to upgrade the mainnet.
On the 4th anniversary of the DAO Bailout Hard Fork, ETH-centric client maintainers orchestrate a social attack on Ethereum Classic. The client maintainers announce deprecation of Ethereum Classic support, then execute a misinformation marketing campaign citing the ETC network would lose 70% of the hashrate among other untruths.
After a year long discussion about whether a ECIP-1098 would gel with ETC values, ETC Coop, followed by IOHK withdraw support for a Treasury Proposal at the network level.
Ethereum Classic commits support to the ETChash mining algorithm and the current mining ecosystem. This positions Ethereum Classic as a network well positioned to absorbed a majority of the disenfranchised Ethash miners with ETH network's move to proof of stake consensus.
Stable and long-term funding proves to be a problem for Ethereum Classic with abandonment by the Ethereum Foundation in 2016. In an effort to solve the network's LTS funding issue, Ethereum Classic DAO is formed with a mission to future proof the network's development via an open source development fund. Funding is generated with use of an ETC DeFi stack hosted at EthereumClassic.com
Ethereum Classic's block rewards are reduced by 20% to 2.56 ETC per block, as per the bitcoin-inspired 5M20 emission schedule. ETChash mining hasrate continues to turn over to ETC with the network reaching All-Time Highs.
After more than three years of contentious debate, Bob Summerwill acknowledges the contentious hardfork ECIP-1049 would cause on the network and withdraws the proposal. The negative social cost caused by the ECIP-1049 proponents misinformation campaign continues to negatively effect the network's public perception. However through its resilient community, Ethereum Classic remains well-positioned to thrive on ETChash in a post-merge world.
Ethereum Classic DAO launches its first product- ETCswap. This ensures the network is one step closer to stable funding for open source development on Ethereum Classic. A professional decentralized protocol stack will be deployed on Ethereum Classic.
Vitalik Buterin, Ethereum's most prominent co-founder, gives an endorsement of the original Ethereum network-- Ethereum Classic for those who value Proof-of-Work chains.
As the upcoming Ethereum merge continues to cause excitement within the crypto space, Ethereum Classic (ETC), a sister of Ethereum, has seen an 83% increase in hashrate since June, 2022.
The Ethereum Foundation upgrades the largest EVM network to proof-of-stake consensus. This Merge event cements Ethereum Classic as the largest Proof of Work EVM network. Ethereum Classic's network security elevates as it becomes the apex network of all Ethash derivative mining algorithms. The Phoenix rises.
As the ecosystem continues to organically grow, the independent development teams and network participants are guided by principles that make Ethereum Classic such a unique network. The network is truly decentralized, immutable, and unstoppable. Code is law.