(CNN) Turkey's President Recep Tayyip Erdogan has steered his country through a period of extraordinary change.

The country's economic rise has been meteoric, lifting millions of people out of poverty, but it's also suffered a stream of deadly terror attacks and a failed military coup last year, which prompted a clampdown on civil liberties.

Turkey in 2017 is a vastly different country to a decade ago and on Sunday, the Turkish people will vote in a referendum on a new constitution that could hand Erdogan unprecedented powers, cementing his position for years to come.

Shifting Turkey away from a parliamentary republic to a presidential one, is at the heart of the proposals, but the vote has also become a plebiscite on Erdogan and his footprint on the country.

What are they voting on?

The 18-article constitutional reform package has been dubbed the "power bill," and would effectively consolidate the authority of three legislative bodies into one executive branch, with the President as its head.

The President would be given the authority to appoint ministers and judges without parliament's approval, design a state budget and dissolve parliament.

Currently, the President's role is supposed to be largely ceremonial, but Erdogan has already broken with tradition and kept himself as the face of Turkey's leadership.

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If the Turkish people vote yes, the country will get rid of all the checks and balances that keep the government in line, according to Esra Ozyurek, the chair for Contemporary Turkish Studies at the London School of Economics.

"Parliament will become totally ineffective, just rubber stamping Erdogan's policies. There will be no prime minister -- all the power will be in Erdogan's hands."

Erdogan has essentially ruled Turkey for more than 13 years -- he rose to power as prime minister in 2003 and stayed in that position until he was elected president in 2014.

"Erdogan clearly has charismatic aspects -- the people who love him love him so much, and people who hate him, they hate him intensely," Ozyurek said.

"It's rare to meet anyone without strong feelings toward him."

Erdogan has argued that creating a presidential system would bring "stability and confidence" to Turkey, state-run media Anadolu reported.

Women attend a pro-Erdogan rally in Istanbul on July 22, 2016, following the failed military coup.

"Let's make consolidation in this great historic reform and put in place the foundation stones of a strong, leading and prosperous Turkey with unity, solidarity and integrity," he said.

He and his senior ministers have argued that a stronger government is needed to deal with the spate of recent terror attacks.

What's happened since the failed coup?

Extraordinary changes came to Turkey in July 2016, after a failed military coup prompted a purge that reached just about every institution in public life.

According to Turkish state media, 249 people were killed in the coup attempt, and had it been successful, Turkey may have been plunged into civil war.

Although the coup aimed to topple Erdogan, the President himself declared the attempt a "gift from god."

His government subsequently imposed a state of emergency giving him unprecedented powers; this has been extended several times.

The government has detained tens of thousands of Erdogan's political opponents, as well as journalists and civil society groups and removed more than 100,000 people from their jobs, including school teachers and security officers.

Among those imprisoned were the leaders of the main pro-Kurdish Peoples' Democratic Party, as the government continues to stamp out Kurdish opposition.

The purge also targeted anyone with links to Fethullah Gulen, Erdogan's friend-turned-rival, who lives in the United States in exile.

"People are afraid to talk. You can get in a taxi and complain about Erdogan, and the driver might record you and take you to the police," Ozyurek said.

"I've heard of activists going to the beach and swimming out to sea so they can have a frank conversation without being heard."

The Turkish people had already seen a forceful response from the government, when a 2013 peaceful sit-in over plans to demolish the Gezi Park in central Istanbul turned into a nationwide protest movement against Erdogan, who was then prime minister.

At least five protestors and a police officer were killed in clashes, and thousands were injured, according to Human Rights Watch . Erdogan eventually admitted police had used excessive force in the protests.

Who supports Erdogan?

Many of Erdogan's most loyal supporters come from Turkey's rising middle class, whose lives have transformed in the country's economic boom.

The average person's income has risen from $3,800 in 2003, when Erdogan became prime minister, to around $10,000 in 2017, according to data from the World Bank . This means the number of people living below the poverty line dropped from 23% of the population to less than 2% in that time.

"Now the middle class has a different lifestyle. If you take today a couple in their 30s with two kids, and compare them with another couple 10 years ago, they live a different life," said Marc Pierini, a visiting scholar at Carnegie Europe, who served as EU ambassador to Turkey from 2006 to 2011.

Pierini said that when Erdogan became prime minister, his government had adopted the wave of reforms from its predecessors and "got their act together," bringing infrastructure and services to the regions.

The government also made credit more easily available to the middle class.

"Today's couple has an apartment -- of course with a mortgage. They have a car -- of course with credit. They go to shopping centers and they travel. They can take a domestic airline that didn't exist until 2008," he said.

How has Turkey responded to the terror threat?

Turkey has also been changed by a series of terror attacks, which some see as a failure by the government to manage long-standing tensions with Kurdish groups and to deal with the Syria conflict on its doorstep.

The US and other countries have long called on Turkey to seal its border with Syria, as ISIS appears to have used Turkey as thoroughfare to smuggle people and resources in and out of Syria.

Almost all recent attacks in Turkey have been blamed on either ISIS or the Kurdistan Workers Party (PKK).

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Turkey has beefed up its security and launched an anti-ISIS military campaign in Syria, but the attacks have already taken a toll on the country

"Tourism in Turkey is in shambles," Ozyurek said. "It is one of the biggest industries, but now all the hotels are empty. And who would want to come to a country where it doesn't feel safe?"

She said that this change was felt profoundly in Istanbul, particularly since a New Year's terror attack at a nightclub in which dozens were killed.

"There used to be a thriving urban nightlife, but not now. It's no longer the cheerful happy city it once was."

Where is Turkey heading?

What's clear is its role as a bridge between the West and the Islamic east is changing.

Modern Turkey was built on a foundation of political secularism, but in the past decade, the influence of Islam has crept into Turkish political discourse and policy

And the country now appears to be turning away from the West.

Turkey applied to become a member of the European Union in 1987. Negotiations only began in 2005 and talks have since hit a wall.

Istanbul residents walk past "Yes" campaign signs in the city center on Saturday, April 8, 2017.

A stark example is Erdogan's suggestion that his country might bring back the death penalty, which would instantly disqualify the country for membership.

If the Turkish people vote "Yes" on Sunday, the country is in for yet another decade of change.