Ethereum has undergone a remarkable transformation since its inception, evolving from a nascent blockchain platform into a robust, scalable, and secure foundation for decentralized applications. As the network prepares for the highly anticipated Cancun upgrade in 2025, it’s essential to understand the pivotal milestones that shaped its journey. This article explores Ethereum’s 12 most significant upgrades—from Frontier to Shanghai—highlighting their technical impact, economic implications, and role in advancing the ecosystem.
Whether you're a developer, investor, or enthusiast within the Ethereum ecosystem, grasping this historical progression offers valuable context for future developments.
The Nature of Blockchain Upgrades
Unlike traditional software that rolls out updates via centralized releases, blockchain networks like Ethereum rely on forks to implement changes. Since there is no central authority, upgrades require consensus among validators and node operators. When an upgrade occurs, nodes must update their software to follow new rules; otherwise, they risk operating on an obsolete chain.
Most upgrades are planned hard forks, where the network smoothly transitions to a new protocol version. However, contentious decisions—like the 2016 DAO fork—can result in permanent splits, such as ETH vs. ETC (Ethereum Classic).
Now, let’s walk through Ethereum’s major milestones.
1. Frontier – July 30, 2015
Frontier marked Ethereum’s official launch as a functional but minimalistic proof-of-work (PoW) network. Designed for developers, it lacked a graphical interface and operated primarily through command-line tools—akin to a beta release.
Initially, each block was hardcoded with a gas limit of just 5,000, severely restricting transaction capacity. Two months later, the Frontier Thawing update removed this cap and set the default gas price at 50 gwei. Crucially, this release also introduced the difficulty bomb—a mechanism designed to gradually increase mining difficulty over time, eventually making PoW unsustainable and paving the way for the transition to proof-of-stake (PoS).
At launch, ETH traded at approximately $1.24.
👉 Discover how Ethereum’s early design decisions shaped its future scalability.
2. Homestead – March 14, 2016
Homestead represented Ethereum’s first stable release, signaling a shift from experimental phase to production readiness. It was the first upgrade to formally adopt Ethereum Improvement Proposals (EIPs)—a governance framework still in use today.
Key EIPs included:
- EIP-2: Raised contract creation cost from 21,000 to 53,000 gas.
- EIP-7: Introduced
DELEGATECALL, enabling better code reuse in smart contracts. - EIP-8: Enhanced network protocol compatibility.
This upgrade solidified Ethereum as a viable platform for building decentralized applications (dApps). At the time, ETH was valued at around $12.50.
3. The DAO Fork – July 20, 2016
Not a planned upgrade, but a critical response to one of blockchain’s most infamous events: the DAO hack.
The DAO—a decentralized autonomous organization—raised over $150 million in ETH during a record-breaking ICO. However, a vulnerability in its smart contract allowed an attacker to drain nearly a third of its funds. After failed attempts to recover the assets organically, the community voted to execute a hard fork, reversing the theft.
While effective, this decision sparked intense debate about immutability and decentralization. A faction opposed to the intervention continued supporting the original chain, now known as Ethereum Classic (ETC).
ETH price post-fork: $12.54
4. Byzantium – October 16, 2017
Byzantium was the first phase of the broader Metropolis upgrade. With ten EIPs implemented, it enhanced privacy, efficiency, and security.
Notable changes:
- EIP-649: Reduced block reward from 5 ETH to 3 ETH.
- Delayed the difficulty bomb by 1.5 years due to PoS not being ready.
- EIP-214: Improved security by restricting state modifications during contract calls.
These adjustments reflected Ethereum’s long-term strategy: gradually reduce PoW incentives to ease the transition to PoS.
ETH price: $334.32
5. Constantinople (and St. Petersburg) – February 28, 2019
Originally scheduled earlier, Constantinople was delayed due to a discovered vulnerability. When finally deployed alongside St. Petersburg (a security patch), it furthered Ethereum’s move toward PoS.
Key features:
- EIP-1234: Cut block rewards from 3 ETH to 2 ETH.
- Delayed the difficulty bomb by another year.
- EIP-1014: Introduced
CREATE2, enabling pre-computed contract addresses—critical for state channels and Layer 2 scaling solutions like zkRollups.
ETH price: $136.29
6. Muir Glacier – January 2, 2020
An emergency upgrade triggered by miscalculations around the difficulty bomb’s timing. To prevent premature “ice age” conditions (where mining becomes too slow), Muir Glacier delayed the bomb by an additional four million blocks (~1 year).
Unlike other Metropolis-era upgrades named after cities, this one broke tradition—named after a vanished Alaskan glacier, symbolizing the deferral of Ethereum’s frozen PoW future.
ETH price: $127.18
7. Beacon Chain Launch – December 1, 2020
The cornerstone of Ethereum’s PoS future: the Beacon Chain went live. Though initially running parallel to the PoW mainnet without processing user transactions, it laid the foundation for validator staking and consensus coordination under PoS.
Over 586,000 ETH were staked at launch. This marked the beginning of “Phase 0” in Ethereum 2.0’s roadmap.
ETH price: $586.23
8. Berlin – April 15, 2021
Berlin ushered in a new naming convention: future upgrades would be named after cities that hosted Devcon conferences. This upgrade optimized gas costs for certain transaction types and improved cross-chain interoperability.
Four EIPs were implemented, focusing on network efficiency ahead of larger scalability overhauls.
ETH price: $2,454
9. London – August 5, 2021
London introduced EIP-1559, arguably one of Ethereum’s most transformative upgrades.
It reformed transaction pricing by:
- Introducing a base fee that is burned rather than paid to miners.
- Creating a more predictable fee market.
- Turning ETH into a deflationary asset during periods of high usage.
To date, over 3.2 million ETH (~$6 billion) has been burned. This shift significantly altered Ethereum’s economic model and increased investor confidence.
ETH price: $2,621
10. Paris (The Merge) – September 15, 2022
The historic Merge transitioned Ethereum from PoW to PoS consensus—a seven-year journey culminating in one seamless upgrade.
Key outcomes:
- Energy consumption dropped by ~99.95%.
- Beacon Chain became the new consensus engine.
- Block rewards replaced by staking yields.
However, one limitation remained: no withdrawal capability for staked ETH—prompting demand for liquid staking derivatives like Lido and Rocket Pool.
ETH price: $1,472
11. Shanghai – April 12, 2023
Shanghai unlocked stake withdrawals, allowing validators to finally exit and reclaim their ETH after years of lock-up.
This restored full liquidity to staked assets and boosted participation in decentralized finance (DeFi) through emerging Liquid Staking Derivatives Finance (LSDFi) protocols.
Post-upgrade, over 19 million ETH were staked on-chain.
ETH price: $1,917
12. Cancun Upgrade – Expected Late 2025
The upcoming Cancun upgrade focuses on scaling Layer 2 networks via proto-danksharding.
Central feature:
- EIP-4844: Introduces blob-carrying transactions, allowing L2 rollups to store data off the main chain at drastically reduced costs—potentially lowering L2 fees by up to 90%.
This paves the way for full danksharding in later phases, positioning Ethereum as a truly scalable base layer for global dApp adoption.
👉 Explore how EIP-4844 will revolutionize Layer 2 economics and user accessibility.
Frequently Asked Questions (FAQ)
Q: What is the purpose of Ethereum’s difficulty bomb?
A: The difficulty bomb gradually increases mining difficulty to make proof-of-work unsustainable, incentivizing the transition to proof-of-stake.
Q: How did EIP-1559 change Ethereum’s economy?
A: By burning part of every transaction fee, EIP-1559 introduced deflationary pressure on ETH supply during high network activity.
Q: Why was The DAO fork controversial?
A: It challenged the principle of immutability—altering history via a hard fork raised concerns about centralization and precedent-setting.
Q: What is proto-danksharding?
A: A scalability solution using blob transactions (via EIP-4844) to reduce data load on Layer 1 while supporting cheaper Layer 2 operations.
Q: Can I still mine Ethereum after The Merge?
A: No—after September 2022, Ethereum fully transitioned to proof-of-stake; mining is no longer possible on the mainnet.
Q: What are LSDFi protocols?
A: Liquid Staking Derivatives Finance combines staked ETH tokens (like stETH) with DeFi strategies to unlock liquidity and yield opportunities.
Core Keywords
Ethereum upgrades, Cancun upgrade, EIP-4844, Layer 2 scaling, proof-of-stake, The Merge, EIP-1559, Beacon Chain
With each upgrade, Ethereum has moved closer to its vision of a secure, scalable, and sustainable decentralized world computer. As we approach the Cancun era, Layer 2 innovation will accelerate—bringing blockchain technology within reach of billions.
👉 Stay ahead of Ethereum’s next evolution with real-time data and insights.