Backlinks and SEO: 30 years of evolution, and why they still matter in 2026

I built my first web agency in 2002. SEO back then was raw mechanics: content, tags, and a lot of links. Way, way too many links.

24 years later, almost everything has changed in how Google evaluates a site. Except one thing: inbound links, backlinks, remain one of the most important signals for ranking. Not the same way as before, not with the same raw weight, not with the same tactics. But the fundamental principle still holds: when another site cites you, that is a vote.

Here is the timeline, as I watched it unfold from the seat of my first agency office.

1996 — BackRub: where it all started

Larry Page and Sergey Brin, PhD students at Stanford, started a research project they called BackRub. The idea: rank web pages by their inbound links, their backlinks. The project name comes literally from that.

What they proposed was radical for the time. Search engines like AltaVista, Lycos, or Excite ranked pages based on internal content (keywords, frequency, tags). Page and Brin said: no, the real signal of relevance is what other sites think. A link from one site to another is a recommendation.

1998 — PageRank and the birth of Google

The PageRank patent was filed on January 9, 1998. In September of the same year, Google Inc. was founded. The methodology: each inbound link counts as a vote, weighted by the authority of the site issuing it. A link from NASA is worth more than a link from an obscure blog.

This idea of links as weighted votes has remained the backbone of Google ranking for 30 years.

2000-2010 — The golden age, and industrial cheating

In 2000, Google released the Toolbar, which publicly displayed every page PageRank on a 0-10 scale. Major strategic mistake: everyone started chasing the score.

This is the era I lived through with both hands in the engine. Link farms, massive reciprocal exchanges, bulk link buying, blog comment spam, link wheels, satellite sites. An entire industry was built around manipulation. And it worked. For a while.

SEO had largely become a war of volume. Whoever could point 50,000 links to their page won, regardless of quality.

2012 — Penguin restored order, brutally

On April 24, 2012, Google rolled out the Penguin update. Target: manipulative link-building practices. About 3.1% of English queries were affected in the first wave alone.

I remember the weeks that followed very well. Sites that had been ranking for years disappeared in 48 hours. Companies went bankrupt. Entire SEO strategies became, overnight, not just useless but actively harmful.

Penguin was followed by several iterations between 2012 and 2016, each refining the detection of artificial patterns.

The real winners in SEO are not those who accumulated the most links. They are the ones who understood, at each cycle, what Google would value next.

2016 — Penguin goes real-time

In September 2016, Google announced that Penguin 4.0 was integrated into the core algorithm and operating in real-time. No more waiting for an update to penalize or rehabilitate a site. And an important philosophical shift: instead of penalizing sites with bad links, the algorithm started ignoring those links.

Subtle but huge. Bad links went from "danger" to "non-event." The focus shifted definitively toward quality.

2018 — The PageRank patent expires

The original patent expired in 2018. Anecdotal in practical terms, Google had long since evolved well beyond the original PageRank, but symbolic. The method that built Google entered the public domain at the exact moment Google was publicly distancing itself from it.

2022-2024 — "Less important"

Something shifted in Google official messaging. John Mueller, in 2022: "over time, the weight on links will drop off a little bit". In March 2024, Google quietly removed the word "important" from its documentation on links. In April 2024, Mueller at SERP Conf in Sofia: "we need very few links to rank pages... over the years we have made links less important".

Many in the industry interpreted this as: backlinks are dead.

It is wrong. Independent studies in 2024-2025 (Backlinko, Semrush, Ahrefs) all continue to show a strong correlation between link profile and ranking. What Google says and what the data shows are two different things. As often.

2025-2026 — Backlinks become a signal for AI too

This is the most interesting development of recent years. With the arrival of Google AI Overviews, ChatGPT Search, and Perplexity, the role of backlinks expands.

LLMs do not generate their answers in a vacuum. They rely on sources. And to decide which sources are trustworthy, they use, among other things, the same signals Google has used for 30 years: who points to this content? With what authority? In what topical context?

A site with a strong link profile is more likely to appear in AI Overviews, be cited by ChatGPT and Perplexity, and be considered a reliable source by the models. Backlinks are no longer just a vote for Google. They are a vote for the entire search ecosystem, AI included.

Why backlinks remain essential, and will continue to be

Three reasons, in 2026 and for the foreseeable future.

1. It is an external trust signal, with no substitute

Everything else, content quality, technical, UX, can be manipulated by the site owner. Links come from outside. It is the only signal that fundamentally relies on the opinion of other actors. For that reason alone, they will remain valuable.

2. AI needs them to validate its answers

The more search engines become generative, the more they need mechanisms to distinguish true from false. Authority links are one of the best heuristics available. ChatGPT and Google know this.

3. Competition is less fierce than before

Paradoxically, since everyone is saying "backlinks are dead," fewer competitors are seriously investing in them. This is exactly when a clean link strategy becomes a differentiating advantage.

What this changes for your strategy in 2026

Three principles I apply at Kasvu with the professional service firms we work with.

1. Relevance before raw authority

A link from a site specialized in your sector, even with a moderate Domain Rating, is worth more than a link from a major generalist outlet unrelated to your activity. It is the same logic we find in the seven questions to ask a digital agency before signing.

2. Brand mentions count

Google now identifies entities (brands, people, places) even without a clickable link. A mention in a relevant article passes part of the signal a link would have passed.

3. Moderate volume, high quality

10 real editorial links in relevant contexts beat 1,000 automated links. Detection tools are now excellent: aiming for volume is painting a target on your back.

Wrapping up

The SEO of 2002 and the SEO of 2026 share few tactics. But they share one principle: inbound links are an external trust signal, and that signal is extraordinarily hard to fabricate artificially at scale without leaving traces.

Things will keep changing. The relative weight of links will probably continue to drop. Entity signals, user engagement, LLM citations will gain importance. But 30 years after BackRub, the fundamental principle still holds. It is a pattern I have often seen across the three tech cycles I have lived through.

If I had to bet on the next 5 years: backlinks remain a top-3 or top-5 ranking signal. Not the absolute priority, not the silver bullet, but a pillar that has not found its replacement.

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